<PAGE>
                        SOUTHERN PERU COPPER CORPORATION


                          REGISTRATION RIGHTS AGREEMENT




                           Dated as of March 31, 2005
<PAGE>
                                                                               .
                                                                               .
                                                                               .
                                TABLE OF CONTENTS

            THIS TABLE OF CONTENTS IS NOT PART OF THE AGREEMENT TO WHICH IT IS
ATTACHED BUT IS INSERTED FOR CONVENIENCE ONLY.

<TABLE>
<CAPTION>
                                                                                 Page
                                                                                  No.
                                                                                  ---
<S>                                                                              <C>
1.    Definitions...........................................................       1

2.    Registrations.........................................................       6
      (a)   Shelf Registration..............................................       6
      (b)   Registration Expenses...........................................       6
      (c)   Registration Statement Form.....................................       6
      (d)   Black-Out Periods...............................................       7

3.    Requests for Public Offering; Offerings by Selling Stockholders.......       7
      (a)   Initial Six-Month Period Sales..................................       7
      (b)   Requested Public Offerings......................................       8
      (c)   Limitations on Requested Public Offerings.......................       8
      (d)   Sales by Cerro Entities.........................................       9
      (e)   Sales by PD Entities............................................       9
      (f)   Priority in Cutback Registrations...............................       9
      (g)   Representations, Warranties and Other Agreements................      10

4.    Registration Procedures...............................................      11

5.    Underwritten Offerings................................................      15

6.    Lockup Agreements.....................................................      16
      (a)   By the Selling Stockholders and Permitted Transferees...........      17
      (b)   By the Company..................................................      17
      (c)   By AMC..........................................................      18

7.    Indemnification.......................................................      18
      (a)   Indemnification by the Company..................................      18
      (b)   Indemnification by the Sellers..................................      19
      (c)   Notices of Claims, etc..........................................      19
      (d)   Contribution....................................................      20
      (e)   Other Indemnification...........................................      21

8.    Termination...........................................................      21

9.    Conditions to Obligations of Company and AMC..........................      21

10.   Miscellaneous.........................................................      21
      (a)   Notices.........................................................      21
      (b)   Entire Agreement................................................      23
</TABLE>

                                      - i -
<PAGE>
<TABLE>
<S>                                                                              <C>
      (c)   Amendment.......................................................      23
      (d)   Waiver..........................................................      23
      (e)   Consents and Waivers............................................      23
      (f)   Third Party Beneficiary.........................................      23
      (g)   Comparable Agreements...........................................      24
      (h)   Successors and Assigns..........................................      24
      (i)   Headings........................................................      24
      (j)   Invalid Provisions..............................................      24
      (k)   Remedies........................................................      24
      (l)   Governing Law...................................................      25
      (m)   Counterparts....................................................      25
</TABLE>

Schedule I - Ownership of Class A Common Stock

EXHIBIT A - PLAN OF DISTRIBUTION
EXHIBIT B - RESTRICTED LEGEND
EXHIBIT C-1 - FORM OF OPINION OF CERRO SPECIAL COUNSEL
EXHIBIT C-2 - FORM OF OPINION OF PD SPECIAL COUNSEL




                                     - ii -
<PAGE>
                        SOUTHERN PERU COPPER CORPORATION

                          REGISTRATION RIGHTS AGREEMENT

            This REGISTRATION RIGHTS AGREEMENT dated as of March 31, 2005 is
made and entered into by and between CERRO TRADING COMPANY, INC., a Delaware
corporation ("Cerro"), SPC Investors, L.L.C., a Delaware limited liability
company ("SPC"), PHELPS DODGE CORPORATION, a Delaware corporation ("PD"), PHELPS
DODGE OVERSEAS CAPITAL CORPORATION, a Delaware corporation ("PDOCC"), and CLIMAX
MOLYBDENUM B.V., a Dutch corporation ("Climax"), SOUTHERN PERU COPPER
CORPORATION, a Delaware corporation (the "Company") and AMERICAS MINING
CORPORATION, a Delaware corporation ("AMC"). Capitalized terms not otherwise
defined herein have the meanings set forth in Section 1.

            WHEREAS, AMC, an affiliate of the Company, and Cerro have entered
into a letter agreement dated October 21, 2004 (the "Cerro Letter Agreement")
providing, among other things, for AMC to use its reasonable best efforts to
cause the Company to enter into this Agreement providing for the Company's
registration for sale of certain shares of Common Stock owned by Cerro;

            WHEREAS, AMC and PD have entered into a letter agreement dated
December 22, 2004 (the "PD Letter Agreement") providing, among other things, for
AMC to use its reasonable best efforts to cause the Company to enter into this
Agreement providing for the Company's registration for sale of certain shares of
Common Stock owned by PD;

            NOW, THEREFORE, in consideration of the mutual covenants and
agreements set forth in this Agreement, and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereto agree as follows:

            1. Definitions.

            (a) Except as otherwise specifically indicated, the following terms
will have the following meanings for all purposes of this Agreement:

            "Affiliate" of any particular Person means any other Person
controlling, controlled by, or under common control with such particular Person,
where "control" means the possession, directly or indirectly, of the power to
direct the management and policies of a Person, whether through the ownership of
voting securities, by contract or otherwise.

            "Agreement" means this Registration Rights Agreement, as the same
shall be amended from time to time.

            "AMC" has the meaning ascribed to it in the recitals.

            "Black-Out Period" has the meaning ascribed to it in Section 2(d).

            "Business Day" means a day other than Saturday, Sunday or any other
day on which banks located in the States of Arizona or New York are authorized
or obligated to close.
<PAGE>
            "Cerro" has the meaning ascribed to it in the preamble.

            "Cerro Entities" means, collectively, Cerro, SPC and each of their
respective Permitted Transferees.

            "Cerro Letter Agreement" has the meaning ascribed to it in the
preamble.

            "Cerro Special Counsel" has the meaning ascribed to it in Section
3(g)(ii).

            "Class A Common Stock" means shares of Class A Common Stock, par
value one cent ($0.01) per share, of the Company.

            "Climax" has the meaning ascribed to it in the preamble.

            "Commission" means the United States Securities and Exchange
Commission, or any successor governmental agency or authority.

            "Common Stock" means shares of Common Stock, par value one cent
($0.01) per share, of the Company.

            "Company" has the meaning ascribed to it in the preamble.

            "Company Indemnitees" has the meaning ascribed to it in Section
7(a).

            "Cutback Registration" means any Requested Public Offering to be
effected during the Initial Six-Month Period as an Underwritten Public Offering
in which the Managing Underwriter selected by the Company with respect thereto
advises the Company, the Selling Stockholders and any Permitted Transferees in
writing that, in its opinion, the aggregate number of Registrable Securities
owned by the Selling Stockholders and the Permitted Transferees that have
elected to participate in such Requested Public Offering pursuant to Sections
3(a) and 3(b)(ii) exceeds the number of Registrable Securities which can be sold
in such Underwritten Public Offering without causing a significant disruption in
the market for shares of the Common Stock.

            "Effective Time" has the meaning ascribed to it in the Merger
Agreement.

            "Effectiveness Date" means the date upon which the Shelf
Registration Statement becomes effective under the Securities Act.

            "Exchange Act" means the Securities Exchange Act of 1934, as
amended, and the rules and regulations promulgated thereunder.

            "Form S-3" means Form S-3 promulgated by the Commission under the
Securities Act, or any successor or similar short-form registration statement.

            "Indemnified Party" means a party entitled to indemnity in
accordance with Section 7.

                                     - 2 -
<PAGE>
            "Indemnifying Party" means a party obligated to provide indemnity in
accordance with Section 7.

            "Initial Six-Month Period" means the period commencing on the
Effectiveness Date and ending on the six-month anniversary of the Effectiveness
Date; provided, that such period shall be extended, if applicable, pursuant to
the last paragraph of Section 4.

            "Inspectors" has the meaning ascribed to it in Section 4(h).

            "Losses" has the meaning ascribed to it in Section 7(a).

            "Managing Underwriter" means, with respect to any Underwritten
Public Offering, a single underwriter designated by the Company in accordance
with Section 5 from among the underwriters managing such Underwritten Public
Offering.

            "Merger Agreement" means the Agreement of Plan and Merger dated as
of October 21, 2004, by and among Southern Peru Copper Corporation, SPCC Merger
Sub, Inc., Americas Sales Company, Inc., Americas Mining Corporation and Minera
Mexico S.A. de C.V.

            "NASD" means the National Association of Securities Dealers.

            "PD" has the meaning ascribed to it in the recitals.

            "PD Entities" means Climax and PDOCC and each of their respective
Permitted Transferees.

            "PD Letter Agreement" has the meaning ascribed to it in the
recitals.

            "PDOCC" has the meaning ascribed to it in the preamble.

            "PD Special Counsel" has the meaning ascribed to it in Section
3(g)(ii).

            "Permitted Transferee" has the meaning ascribed to it in Section
6(a).

            "Person" means any natural person, corporation, general partnership,
limited partnership, proprietorship, other business organization, trust, union
or association.

            "Plan of Distribution" has the meaning ascribed to it in Section
2(a).

            "Public Offering" means any offering of Common Stock to the public,
including Requested Public Offerings, either on behalf of the Company or any of
its securityholders, pursuant to an effective registration statement under the
Securities Act.

            "Records" has the meaning ascribed to it in Section 4(h).

            "Registrable Securities" means (i) the Shares, (ii) shares of the
Class A Common Stock, (iii) any additional shares of Common Stock or other
equity securities issued or distributed by way of a stock dividend, stock split,
reclassification, reorganization, recapitalization, other distribution or other
similar event in respect of the Shares, or acquired by

                                     - 3 -
<PAGE>
way of any rights offering or similar offering made in respect of the Shares and
(iv) any equity securities of the Company or any successor or assign of the
Company (whether by merger, consolidation, sale of assets or otherwise) that may
be issued in conversion of, in exchange for or in substitution of, the Shares or
the Class A Common Stock (adjusted proportionately to reflect any stock
dividend, stock split, reclassification, reorganization or recapitalization
occurring after the date hereof). As to any particular Registrable Securities,
such securities shall cease to be Registrable Securities (a) when a registration
statement with respect to the sale of such securities shall have become
effective under the Securities Act and such securities shall have been disposed
of in accordance with such registration statement, (b) when they shall have been
distributed to the public pursuant to Rule 144, (c) when they are transferred to
or become owned by a Person other than a Selling Stockholder (or a Person that
is a successor to all of such Selling Stockholder's rights and obligations
hereunder pursuant to Section 10(h)) or a Permitted Transferee, (d) when they
shall have ceased to be outstanding or (e) upon the Termination Date.

            "Registration Expenses" means all expenses incident and directly
attributable to the Company's performance of or compliance with its obligations
under this Agreement to effect the registration and sale of Registrable
Securities, including, without limitation, all registration, filing, securities
exchange listing and NASD fees, all registration, filing, qualification and
other fees and expenses of complying with securities or blue sky laws, all word
processing, duplicating and printing expenses, messenger and delivery expenses,
the fees and disbursements of counsel for the Company and of its independent
public accountants, including the expenses of any special audits or "cold
comfort" letters required by or incident and directly attributable to such
performance and compliance, the fees and disbursements of counsel retained by
the Selling Stockholders, the Permitted Transferees or any of them, expenses
incurred by the Company in connection with arranging, preparing for, and
participating in, road show presentations and all other selling efforts and any
fees and disbursements of underwriters, including underwriting discounts and
commissions and transfer taxes, if any, in respect of Registrable Securities,
provided that Registration Expenses shall not include (i) salaries of Company
personnel or general overhead expenses of the Company, (ii) auditing fees or
(iii) other expenses (A) for the preparation of regular periodic financial
statements or other data normally prepared by the Company in the ordinary course
of its business or (B) which the Company would have incurred in any event.

            "Representatives" has the meaning ascribed to it in Section 7(a).

            "Requested Public Offering" has the meaning ascribed to it in
Section 3(a).

            "Restated Certificate of Incorporation" means the Restated
Certificate of Incorporation of the Company, as amended.

            "Restricted Legend" has the meaning ascribed to it in Section
3(g)(ii).

            "Rule 144" means Rule 144 promulgated by the Commission under the
Securities Act, and any successor provision thereto.

            "Second Six-Month Period" means the period commencing on the day
after the expiration of the Initial Six-Month Period and ending on the six-month
anniversary of such day.

                                     - 4 -
<PAGE>
            "Securities Act" means the Securities Act of 1933, as amended, and
the rules and regulations promulgated thereunder.

            "Seller Indemnitees" has the meaning ascribed to it in Section 7(b).

            "Selling Stockholders" means Cerro, Climax, PDOCC and SPC.

            "Shares" means (x) the shares of Class A Common Stock, if any, owned
by each of the Selling Stockholders (including all such shares of Class A Common
Stock, if any, transferred after the date hereof by such Selling Stockholders to
Permitted Transferees) as set forth opposite the name of each such Selling
Stockholder on Schedule I and (y) the shares of Common Stock, if any, issued
pursuant to Section 4.9 of the Restated Certificate of Incorporation, to Selling
Stockholders (or Permitted Transferees) on or after the date hereof upon
conversion of the Class A Common Stock owned by such Selling Stockholders (or
Permitted Transferees) (including all such shares of Class A Common Stock, if
any, transferred after the date hereof by such Selling Stockholders to Permitted
Transferees).

            "Shelf Registration" means any registration of Registrable
Securities under the Securities Act effected in accordance with Section 2.

            "Shelf Registration Statement" has the meaning ascribed to it in
Section 2(a).

            "SPCC Sponsorship Period" means the period beginning on the
Effective Time and ending on the last day of the Initial Six-Month Period;
provided, however, if the Initial Six-Month Period has not commenced on or prior
to the eight-month anniversary of the Effective Time, the SPCC Sponsorship
Period shall end on such eight-month anniversary of the Effective Time.

            "Suspension" has the meaning ascribed to it in Section 2(c).

            "Termination Date" has the meaning ascribed to it in Section 8.

            "Underwritten Public Offering" means any offering of Common Stock to
the public, including Requested Public Offerings, either on behalf of the
Company or any of its securityholders, pursuant to an effective registration
statement under the Securities Act and in which such Common Stock is sold to an
underwriter or underwriters on a firm commitment basis for reoffering to the
public pursuant to an underwriting agreement signed by the Company.

            (b) Unless the context of this Agreement otherwise requires, (i)
words of any gender include each other gender; (ii) words using the singular or
plural number also include the plural or singular number, respectively; (iii)
the terms "hereof," "herein," "hereby" and derivative or similar words refer to
this entire Agreement; and (iv) the term "Section" refers to the specified
Section of this Agreement. Whenever this Agreement refers to a number of days,
such number shall refer to calendar days unless Business Days are specified.


                                     - 5 -
<PAGE>
            2. Registrations.

            (a) Shelf Registration. Subject to the provisions of Section 9, the
Company will file as promptly as practicable, and in any event will use its
reasonable best efforts to file with the Commission within 20 Business Days,
after the Effective Time a shelf registration statement on Form S-3 promulgated
by the Commission with respect to the resale of all of the Registrable
Securities on a delayed or continuous basis under Rule 415 of the Securities Act
(the "Shelf Registration Statement"). The Shelf Registration Statement will
contain the Plan of Distribution in substantially the form attached hereto as
Exhibit A (the "Plan of Distribution"). Subject to the provisions of Section 9,
the Company will use its reasonable best efforts to cause the Shelf Registration
Statement to be declared effective as promptly as practicable after the
Effective Time and to remain effective for a period beginning on the
Effectiveness Date and ending on the last day of the Second Six-Month Period.

            (b) Registration Expenses. All reasonable and customary Registration
Expenses incurred in connection with the Shelf Registration (whether or not the
Effectiveness Date occurs or any sales of Registrable Securities are effected
thereunder) and, except as expressly provided in the following sentence, all
other reasonable and customary Registration Expenses shall be (i) paid by the
Selling Stockholders and any Permitted Transferees from time to time promptly
after any request therefore by the Company and (ii) allocated among the Selling
Stockholders and any Permitted Transferees pro rata on the basis of the
respective amounts of Registrable Securities owned by each Selling Stockholder
and Permitted Transferee on the date of any such request. Furthermore, all
reasonable and customary Registration Expenses incurred in connection with any
single Requested Public Offering shall be paid upon closing of such Requested
Public Offering and shall be allocated among the Selling Stockholders and any
Permitted Transferees participating in such Requested Public Offering pro rata
on the basis of the respective amounts of securities then being sold on behalf
of such Selling Stockholders and Permitted Transferees in such Requested Public
Offering.

            (c) Registration Statement Form. Notwithstanding anything to the
contrary contained in this Agreement, if at any time the Company is not eligible
to use Form S-3 promulgated by the Commission for the registration of the
Registrable Securities for sale in accordance with the Plan of Distribution (or
a successor form that permits incorporation by reference of reports and
documents filed under the Exchange Act on a basis comparable to Form S-3), the
Company will so notify the Selling Stockholders and the Permitted Transferees in
writing and the use of the Shelf Registration Statement and the related
prospectus will be automatically suspended (a "Suspension") until such time as
the Company eligible to use Form S-3 (or such successor form). The Company will
not be required to register the Registrable Securities on any other form
promulgated by the Commission that does not permit incorporation by reference of
Exchange Act-filed reports and documents on a basis comparable to Form S-3. In
the event of any Suspension, the Company will use its reasonable best efforts to
again become eligible to use Form S-3 (or such successor form) as soon as
reasonably practicable and will promptly notify the Selling Stockholders and the
Permitted Transferees when it does become so eligible; provided that, for the
avoidance of doubt, the Company acknowledges that use of the Shelf Registration
Statement and the related prospectus shall be automatically reinstated without
further action by any party at such time as the Company is again eligible to use
Form S-3 (or such successor form).

                                     - 6 -
<PAGE>
            (d) Black-Out Periods. Notwithstanding anything to the contrary
contained in this Agreement, but without limiting the provisions of paragraph
(c) of this Section 2, the Company may temporarily suspend the use of the Shelf
Registration Statement and the related prospectus, by giving written notice
thereof to the Selling Stockholders and the Permitted Transferees, for one
period during any 360-day period not to exceed thirty (30) days in the aggregate
(the "Black-Out Period") if, in the good faith opinion of the Company's Board of
Directors, (i) the Shelf Registration Statement is not usable because a
prospectus is required, pursuant to Rule 3-05 and Article 11 of the Regulation
S-X (or any successor provisions), to include financial statements in respect of
businesses acquired or to be acquired and pro forma financial statements and
such financial statements are not readily available or (ii) (x) the Company's
ability to complete a pending or planned material debt or equity financing,
licensing arrangement, joint venture, acquisition or disposition of assets or
stock, merger or other material corporate transaction could reasonably be
expected to be materially and adversely affected by any disclosure of such
transaction required as a result of the continued effectiveness of the Shelf
Registration Statement or (y) the continued effectiveness of the Shelf
Registration Statement would require the Company to make public disclosure of
information the public disclosure of which is not otherwise required and could
reasonably be expected to have a material adverse effect on the Company. The
Company will not be required to specify in the written notice to the Selling
Stockholders and the Permitted Transferees the nature of the event giving rise
to any Black-Out Period. In the event of any Black-Out Period, the Company will
use its reasonable best efforts to cause the use of the Shelf Registration
Statement and the related prospectus so suspended to be resumed as promptly as
practicable after delivery of the notice of such Black-Out Period to the Selling
Stockholders and the Permitted Transferees and shall promptly notify the Selling
Stockholders and the Permitted Transferees of such resumption; provided that,
for the avoidance of doubt, the Company acknowledges that use of the Shelf
Registration Statement and the related prospectus shall be automatically
reinstated without further action by any party at the expiration of the
Black-Out Period.

            3. Requests for Public Offering; Offerings by Selling Stockholders.

            (a) Initial Six-Month Period Sales. At any time during the Initial
Six-Month Period, any one or more Selling Stockholder[s] and/or Permitted
Transferee[s] may request that the Company use its reasonable best efforts to
effect one or more Underwritten Public Offerings, which may include customary
"road show" presentations and all other customary selling efforts, all as the
applicable underwriters shall reasonably request (each such requested
Underwritten Public Offering, a "Requested Public Offering") in accordance with
Section 5. During the SPCC Sponsorship Period, Registrable Securities owned by
the Selling Stockholders and Permitted Transferees may only be sold in Requested
Public Offerings that are sponsored by the Company. Except as provided in the
immediately following sentence, any such request[s] for Requested Public
Offerings shall be in writing and delivered by the requesting Selling
Stockholders and/or Permitted Transferees, as applicable, to, or received by,
the Company, and each of the other Selling Stockholders and Permitted
Transferees as applicable, in accordance with Section 10(a). The Selling
Stockholders and Permitted Transferees shall be deemed to have made a request
for a Requested Public Offering at the Effectiveness Date; provided that (x) the
Company shall have notified such Selling Stockholders and Permitted Transferees
of the anticipated Effectiveness Date at least 5 Business Days prior to the time
that the Company submits a request to accelerate effectiveness of the Shelf
Registration Statement to the Commission and neither Cerro nor PD

                                     - 7 -
<PAGE>
notify the Company in writing prior to the Effectiveness Date that they object
to the commencement of a Requested Public Offering on the Effectiveness Date.

            (b) Requested Public Offerings. Subject to the provisions of Section
9 and the limitations set forth in Section 3(c), in the case of each request for
a Requested Public Offering made during the Initial Six-Month Period, the
Company shall:

            (i) use its reasonable best efforts to prepare and file with the
      Commission within (x) 20 Business Days (in the case of the first Requested
      Public Offering) and (y) within 8 Business Days (in the case of any
      subsequent Requested Public Offering) a prospectus supplement or
      post-effective amendment to the Shelf Registration Statement, as
      necessary, to permit the consummation of the applicable Requested Public
      Offering; and

            (ii) permit any other Selling Stockholder and any Permitted
      Transferee to participate in such Requested Public Offering (subject to
      the proviso at the end of this paragraph (b)) if within five Business Days
      of receipt by all of the Company, Cerro and PD of a request for a
      Requested Public Offering from any one or more Selling Stockholder[s]
      and/or Permitted Transferee[s], such other Selling Stockholder and/or
      Permitted Transferee delivers to the Company and each other Selling
      Stockholder and Permitted Transferee written notice in accordance with
      Section 10(a) that it desires to sell its Registrable Securities in such
      Requested Public Offering;

provided that, notwithstanding the foregoing, the number of Registrable
Securities to be sold by the Selling Stockholders and any Permitted Transferees
in connection with a Requested Public Offering shall be determined by the
Managing Underwriter (in consultation with the Company, Cerro and PD) to be the
maximum number of Registrable Securities that may be sold, including in
connection with the exercise by the underwriters of any related over-allotment
options, without causing a significant disruption in the market for shares of
the Common Stock. Notwithstanding anything in this clause (b) to the contrary,
the number of Registrable Securities to be sold in any such Requested Public
Offering shall not be less than 20,000,000, or such lesser amount as the
Managing Underwriter determines can be sold as provided in the previous sentence
(such number of Registrable Securities to be adjusted proportionately to reflect
any stock dividend, stock split, reclassification, reorganization,
recapitalization, distribution or other similar event in respect of the Shares).

            (c) Limitations on Requested Public Offerings. Notwithstanding
anything herein to the contrary, the Company shall not be required to honor a
request for a Requested Public Offering by any one or more Selling
Stockholder(s) or Permitted Transferee(s) if:

            (i) such request for a Requested Public Offering is received by the
      Company after the expiration of the Initial Six-Month Period;

            (ii) the Registrable Securities requested by the Selling
      Stockholders and the Permitted Transferees to be sold in connection with
      such Requested Public Offering does not constitute at least 10,000,000
      Shares (such number of Registrable Securities to be adjusted
      proportionately to reflect any stock dividend, stock split,
      reclassification,

                                     - 8 -
<PAGE>
      reorganization, recapitalization, distribution or other similar event in
      respect of the Shares); provided, however, that, to the extent that the
      aggregate number of remaining Registrable Securities is less than
      10,000,000 at the time a Requested Public Offering is requested, the
      Company shall be required to honor such request for a Requested Public
      Offering; provided further that all such remaining Registrable Securities
      then held by (x) the Cerro Entities (in the case of a request by all or
      any of them) or (y) the PD Entities (in the case of a request by all or
      any of them) are requested to be sold in connection with such Requested
      Public Offering; or

            (iii) such request is received by the Company at any time during the
      Initial Six-Month Period that a Requested Public Offering is in progress,
      regardless of whether the Selling Stockholder or Permitted Transferee
      making such request exercised its rights under this Agreement to
      participate in such Requested Public Offering.

            (d) Sales by Cerro Entities. During the Second Six-Month Period,
each of the Cerro Entities shall have the right to effect sales of Registrable
Securities included in the Shelf Registration Statement in any manner
contemplated in the Plan of Distribution; provided, however, that the Cerro
Entities may not sell more than 1,000,000 Registrable Securities in the
aggregate per calendar month (such 1,000,000 to be adjusted proportionately to
reflect any stock dividend, stock split, reclassification, reorganization,
recapitalization, distribution or other similar event in respect of the Shares).
If the Cerro Entities desire to sell more than 1,000,000 Registrable Securities
in the aggregate in any calendar month pursuant to this Section 3(d), Cerro
shall determine as between the Cerro Entities which of such Registrable
Securities may be sold. The Company shall not have any obligation to enter into
any underwriting agreements or to arrange, prepare for, or participate in, any
"road show" presentations or any other selling efforts in connection with, or
any obligation otherwise with respect to, any offerings of its securities that
may be effected by any Cerro Entity following the expiration of the Initial
Six-Month Period.

            (e) Sales by PD Entities. During the Second Six-Month Period, each
of the PD Entities shall have the right to effect sales of Registrable
Securities included in the Shelf Registration Statement in any manner
contemplated in the Plan of Distribution; provided, however, that the PD
Entities may not sell more than 1,000,000 Registrable Securities in the
aggregate per calendar month (such 1,000,000 to be adjusted proportionately to
reflect any stock dividend, stock split, reclassification, reorganization,
recapitalization, distribution or other similar event in respect of the Shares).
If the PD Entities desire to sell more than 1,000,000 Registrable Securities in
the aggregate in any calendar month pursuant to this Section 3(e), PD shall
determine as between the PD Entities which of such Registrable Securities may be
sold. The Company shall not have any obligation to enter into any underwriting
agreements or to arrange, prepare for, or participate in, any "road show"
presentations or any other selling efforts in connection with, or any obligation
otherwise with respect to, any offerings of its securities that may be effected
by any PD Entity following the expiration of the Initial Six-Month Period.

            (f) Priority in Cutback Registrations. With respect to any Requested
Public Offering effected by the Company during the Initial Six-Month Period, if
such Requested Public Offering becomes a Cutback Registration, the Company will
include in any such Requested Public Offering a number of Registrable Securities
not less than that which the Managing Underwriter determines is the maximum
number of Registrable Securities that may be sold in

                                     - 9 -
<PAGE>
such Requested Public Offering without causing a significant disruption in the
market for shares of the Common Stock, which Registrable Securities shall be
allocated among the Cerro Entities and the PD Entities that have elected to
participate in such Requested Public Offering pro rata on the basis of the
number of Registrable Securities each such Cerro Entity and/or PD Entity owns on
the date that the Managing Underwriter makes such determination. Following the
determination of any such pro rata allocation, each of Cerro and PD shall have
the right to specify what portion of the aggregate Registrable Securities so
allocated to the participating Cerro Entities (in the case of Cerro) and the
participating PD Entities (in the case of PD) may be sold by each such
participating Cerro Entity or PD Entity, as applicable, in connection with such
Cutback Registration.

            (g) Representations, Warranties and Other Agreements.

               (i) Accuracy of Schedule I. The Cerro Entities hereby represent
      and warrant, jointly and severally, to the Company that (x) they do not
      own any shares of Common Stock on the date hereof and (y) with respect to
      the number of shares of Class A Common Stock set forth opposite the names
      of the Cerro Entities on Schedule I, such information is true, accurate,
      complete and correct in all respects on the date hereof. The PD Entities
      hereby represent and warrant, jointly and severally, to the Company that
      (x) they do not own any shares of Common Stock on the date hereof and (y)
      with respect to the number of shares of Class A Common Stock set forth
      opposite the names of the PD Entities on Schedule I, such information is
      true, accurate, complete and correct in all respects on the date hereof.

            (ii) Agreement to Effect Conversion of Class A Common Stock. Each of
      AMC, the Cerro Entities and the PD Entities hereby agrees that, on the
      Effectiveness Date, all shares of Class A Common Stock owned by each such
      Person (or SPHC II Incorporated, in the case of AMC) on such date shall be
      converted in accordance with Sections 4.9(b) and 4.9(c) of the Restated
      Certificate of Incorporation into an equal number of fully paid and
      non-assessable shares of Common Stock. Upon such conversion, the Company
      agrees to issue, or to cause to be issued, and the Cerro Entities and PD
      Entities agree to accept, stock certificates bearing the Restricted Legend
      set forth in Exhibit B hereto and representing the number of shares of
      Common Stock held by each of them, respectively, as of such conversion
      date. Upon the delivery to the Company by (x) Cleary Gottlieb Steen &
      Hamilton LLP or other counsel reasonably acceptable to the Company ("Cerro
      Special Counsel"), as special counsel to the Cerro Entities (with respect
      to certificates representing shares of Common Stock held by one or more of
      the Cerro Entities) or (y) Debevoise & Plimpton LLP or other counsel
      reasonably acceptable to the Company ("PD Special Counsel"), special
      counsel to the PD Entities (with respect to certificates representing
      shares of Common Stock held by one or more of the PD Entities), of a legal
      opinion, which shall be addressed to the Company and, to the extent the
      Company is not acting in such capacity, the Company's transfer agent and
      shall be substantially in the form set forth in Exhibit C-1 (in the case
      of Cerro Special Counsel) or Exhibit C-2 (in the case of PD Special
      Counsel) hereto, as applicable, the Company hereby agrees to issue to the
      Cerro Entities whose shares of Common Stock are the subject of such
      opinion and/or the PD Entities whose shares of Common Stock are the
      subject of such opinion, as applicable, new stock certificates
      representing the number of

                                     - 10 -
<PAGE>
      shares of Common Stock held by each of them as of the date such opinion(s)
      is delivered to the Company, respectively, but without the Restricted
      Legend.

            4. Registration Procedures. In connection with the filing of the
Shelf Registration Statement, the Company will, as promptly as practicable:

            (a) subject to paragraphs (c) and (d) of Section 2, prepare and file
      with the Commission such amendments and supplements to such registration
      statement and any prospectus used in connection therewith as may be
      necessary to maintain the effectiveness of such registration statement and
      to comply with the provisions of the Securities Act with respect to the
      disposition of all Registrable Securities covered by such registration
      statement, in accordance with the Plan of Distribution, until the earlier
      of (i) such time as none of the securities covered by the Shelf
      Registration Statement constitute Registrable Securities and (ii) the
      Termination Date;

            (b) promptly notify the Selling Stockholders and any Permitted
      Transferees:

                  (i) when such registration statement or any prospectus used in
            connection therewith, or any amendment or supplement thereto, has
            been filed and, with respect to such registration statement or any
            post-effective amendment thereto, when the same has become
            effective;

                  (ii) of any written request by the Commission for amendments
            or supplements to such registration statement or prospectus or
            additional information;

                  (iii) of the notification to the Company by the Commission of
            its initiation of any proceeding with respect to the issuance by the
            Commission of, or of the issuance by the Commission of, any stop
            order suspending the effectiveness of such registration statement;
            and

                  (iv) of the receipt by the Company of any notification with
            respect to the suspension of the qualification of any Registrable
            Securities for sale under the applicable securities or blue sky laws
            of any jurisdiction;

            (c) furnish to the Selling Stockholders, any Permitted Transferees
      and any underwriter, such number of conformed copies of such registration
      statement and of each amendment and supplement thereto (in each case
      including all exhibits and documents incorporated by reference), such
      number of copies of the prospectus contained in such registration
      statement (including each preliminary prospectus and any summary
      prospectus) and any other prospectus filed under Rule 424 promulgated
      under the Securities Act, and such other documents, as the Selling
      Stockholders, any Permitted Transferees or any underwriter may reasonably
      request to facilitate the disposition of the Registrable Securities
      covered by such registration statement;

            (d) use its reasonable best efforts to register or qualify all
      Registrable Securities covered by such registration statement under such
      other securities or blue sky laws of

                                     - 11 -
<PAGE>
      such jurisdictions as any Selling Stockholder, any Permitted Transferee or
      any underwriter shall reasonably request, to keep such registration or
      qualification in effect for so long as such registration statement remains
      in effect, and take any other action which may be reasonably necessary or
      advisable to enable any Selling Stockholder, any Permitted Transferee or
      any underwriter to consummate the disposition in such jurisdictions of its
      Registrable Securities covered by such registration statement, except that
      the Company shall not for any such purpose be required (i) to qualify
      generally to do business as a foreign corporation in any jurisdiction
      wherein it would not but for the requirements of this paragraph (d) be
      obligated to be so qualified, (ii) to subject itself to taxation in any
      such jurisdiction or (iii) to consent to general service of process in any
      jurisdiction;

            (e) use its reasonable best efforts to cause all Registrable
      Securities covered by such registration statement to be registered with or
      approved by such other governmental agencies or authorities as may be
      necessary to enable any Selling Stockholder, any Permitted Transferee or
      any underwriter to consummate the disposition of such Registrable
      Securities;

            (f) promptly notify the Selling Stockholders and any Permitted
      Transferees at any time when a prospectus relating thereto is required to
      be delivered under the Securities Act, of the happening of any event
      (other than an event triggering a Suspension or relating to a Black-Out
      Period, which are governed by paragraphs (c) and (d) of Section 2,
      respectively) as a result of which any prospectus included in such
      registration statement, as then in effect, includes an untrue statement of
      a material fact or omits to state any material fact required to be stated
      therein or necessary to make the statements therein, in the light of the
      circumstances under which they were made, not misleading, and at the
      request of any Selling Stockholder or Permitted Transferee promptly
      prepare and furnish to such Selling Stockholders and Permitted Transferees
      a reasonable number of copies of a supplement to or an amendment of such
      prospectus as may be necessary so that, as thereafter delivered to the
      purchasers of such securities, such prospectus shall not include an untrue
      statement of a material fact or omit to state a material fact required to
      be stated therein or necessary to make the statements therein, in the
      light of the circumstances under which they were made, not misleading;

            (g) otherwise use its reasonable best efforts to comply with all
      applicable rules and regulations of the Commission, and make available to
      its securityholders, as soon as reasonably practicable, an earnings
      statement covering the period of at least twelve (12) months, but not more
      than eighteen (18) months, beginning with the first full calendar month
      after the effective date of such registration statement, which earnings
      statement shall satisfy the provisions of Section 11(a) of the Securities
      Act and Rule 158 promulgated thereunder;

            (h) make available for inspection by any underwriter participating
      in any disposition pursuant to such registration statement and any
      attorney, accountant or other agent retained by such underwriter
      (collectively, the "Inspectors"), all financial and other records,
      pertinent corporate documents and properties of the Company (collectively,
      the

                                     - 12 -
<PAGE>
      "Records") as shall be reasonably necessary to enable them to exercise
      their due diligence responsibility, and use its best efforts to cause the
      Company's directors, officers and employees to supply all information
      reasonably requested by any such Inspector in connection with such
      registration statement and use its best efforts to cause the Company's
      directors, officers and employees and independent public accountants who
      have certified its financial statements to make themselves available to
      discuss the business of the Company and to supply all information
      reasonably requested by any such Inspector as shall be necessary to enable
      such Inspector to exercise its due diligence responsibility; provided that
      records which the Company determines, in good faith, to be confidential
      and which it notifies the Inspectors are confidential shall not be
      disclosed by the Inspectors unless (i) the disclosure of such Records is
      necessary to avoid or correct a misstatement or omission in the
      registration statement, (ii) the release of such Records is ordered
      pursuant to a subpoena or other order from a court of competent
      jurisdiction or (iii) the information in such Records has been made
      generally available to the public;

            (i) at the request of any Selling Stockholder or Permitted
      Transferee with respect to any Requested Public Offering requested during
      the Initial Six-Month Period, enter into and perform its obligations under
      any related underwriting agreement with the underwriters of such Requested
      Public Offering (the form of which agreement shall be subject to Section
      5);

            (j) enter into such other agreements and use its reasonable best
      efforts to take such other actions in order to expedite or facilitate the
      disposition of Registrable Securities in connection with any Requested
      Public Offering requested by any Selling Stockholder or Permitted
      Transferee during the Initial Six-Month Period, including, without
      limitation, arranging, preparing for, and participating in, customary
      "road shows" presentations (including to institutional investors,
      analysts, money managers and others) and all other customary selling
      efforts, all as the underwriters shall reasonably request, which
      presentations shall take place in such locations, include such members of
      the Company's management and last for such duration as the Company and the
      underwriters deem appropriate; provided, that in any event such selling
      efforts shall be no less than efforts carried out for other similar
      offerings of securities of the size and complexity involved with such
      Requested Public Offering;

            (k) cooperate with any Selling Stockholder and any Permitted
      Transferee participating in the applicable Requested Public Offering or
      sale and the underwriters, if any, to facilitate the timely preparation
      and delivery of certificates representing Registrable Securities to be
      sold;

            (l) not later than the date of the sale of any Registrable
      Securities pursuant to the Shelf Registration Statement, provide a CUSIP
      number for all Registrable Securities and provide the applicable transfer
      agent with printed certificates for the Registrable Securities which
      certificates shall not bear the Restricted Legend and shall be in a form
      eligible for deposit with The Depository Trust Company;

                                     - 13 -
<PAGE>
            (m) obtain for delivery to any Selling Stockholder and any Permitted
      Transferee participating in the applicable Requested Public Offering or
      sale and to the underwriters, if applicable, an opinion or opinions from
      counsel for the Company dated the Effectiveness Date and, in the event of
      a Requested Public Offering, the date of the closing under the
      underwriting agreement, in customary form, scope and substance, which
      counsel and opinions shall be reasonably satisfactory to Cerro or PD, as
      applicable, and the underwriters, if applicable, and their respective
      counsel;

            (n) in the case of a Requested Public Offering, obtain for delivery
      to the Company and the underwriters with copies to the Selling
      Stockholders and any Permitted Transferees participating in the applicable
      Requested Public Offering, a cold comfort letter from the Company's
      independent certified public accountants in customary form and covering
      such matters of the type customarily covered by cold comfort letters as
      the underwriters reasonably request, dated the date of execution of the
      underwriting agreement and brought down to the closing under the
      underwriting agreement;

            (o) cause all Registrable Securities of a class to be listed on each
      securities exchange on which any of the Company's securities of such class
      are then listed or quoted and on each inter-dealer quotation system on
      which any of the Company's securities of such class are then quoted; and

            (p) at least three days before filing with the Commission, provide
      to each Selling Stockholder and Permitted Transferee drafts of each
      document to be filed in connection with the Shelf Registration Statement
      substantially in the form in which the Company expects such document to be
      filed.

            In the event of the issuance of any stop order suspending the
effectiveness of the Shelf Registration Statement, or any order suspending or
preventing the use of any related prospectus or suspending the qualification of
any Registrable Securities included in the Shelf Registration Statement for sale
in any jurisdiction, the Company will use its reasonable best efforts to
promptly obtain the withdrawal of such order and promptly notify the Selling
Stockholders and any Permitted Transferees of such withdrawal.

            The Company may require each of the Selling Stockholders and each
Permitted Transferee participating in the applicable Requested Public Offering
to, and each Selling Stockholder and each such Permitted Transferee, as a
condition to including Registrable Securities in the Shelf Registration
Statement, shall, furnish the Company with such information and certificates
regarding each such Selling Stockholder and each such Permitted Transferee,
respectively, and the distribution of such securities as the Company may from
time to time reasonably request in writing in connection with such registration.

            In addition, each Selling Stockholder and each Permitted Transferee
participating in the applicable Requested Public Offering or sale, as
applicable, shall (a) agree to furnish to the Company such information regarding
the method of distribution of the shares of Common Stock to be distributed and
such other information relating to such Selling Stockholder and such Permitted
Transferee, as applicable, and the ownership by such Selling Stockholder and
such

                                     - 14 -
<PAGE>
Permitted Transferee of Registrable Securities as the Company may from time to
time reasonably request in writing and such Selling Stockholder and such
Permitted Transferee shall furnish such information to the Company and cooperate
with the Company as reasonably necessary to enable the Company to comply with
the provisions of this Agreement; and (b) sell its Registrable Securities on the
basis provided in any underwriting agreements governing any Requested Public
Offering and shall, subject to Section 5, complete and execute all
questionnaires, powers of attorney, indemnities, underwriting agreements and
other documents required under the terms of such underwriting agreements.

            The Selling Stockholders and any Permitted Transferees agree that
upon receipt of any notice to the Selling Stockholders and such Permitted
Transferees from the Company of the occurrence of a Suspension, a Black-Out
Period or any event of the kind described in paragraph (f) of this Section 4,
such Selling Stockholders and Permitted Transferees will forthwith discontinue
their disposition of Registrable Securities pursuant to the Shelf Registration
Statement until the expiration of the Suspension or Black-Out Period or the
availability of copies of the supplemented or amended prospectus contemplated by
paragraph (f) of this Section 4, as applicable (together with copies of the
supplemented or amended prospectus, if any), and, if so directed by the Company,
will deliver to the Company (at the Company's expense) all copies, other than
permanent file copies, then in their possession of the prospectus relating to
such Registrable Securities current at the time of receipt of the original
notice.

            In the event that the Selling Stockholders and any Permitted
Transferees receive any notice from the Company of the occurrence of a
Suspension, a Black-Out Period or any event of the kind described in paragraphs
(b)(iii), (b)(iv) or (f) of this Section 4, then the Initial Six-Month Period
(if the notice is received during such Period) shall be extended by the number
of days during the period from and including the date of the giving of such
notice to and including the date, as applicable, when the Selling Stockholders
and any Permitted Transferees receive notice from the Company that the
Suspension or Black-Out Period has expired, the stop order has been withdrawn,
the suspension of qualification of Registrable Securities has been withdrawn, or
when copies of the supplemented or amended prospectus as contemplated by
paragraph (f) of this Section 4 have been provided.

            5. Underwritten Offerings.

            (a) Terms of Underwritten Offerings. In the case of any Requested
Public Offering being effected pursuant to the Shelf Registration Statement and
Section 3, the Company shall select the Managing Underwriter and any other
underwriter or underwriters with respect to such offerings, which underwriter or
underwriters shall be reasonably satisfactory to PD and Cerro. Such underwriter
or underwriters will be instructed to effect as broad a distribution of the
Registrable Securities to be sold by them as is reasonably practicable, subject
to the limitations contained in Section 3. If so requested by any Selling
Stockholder or any Permitted Transferee participating in any Requested Public
Offering, the Company shall, in connection with any such Requested Public
Offering, enter into an underwriting agreement in customary form with such
underwriter or underwriters, which shall be reasonably satisfactory to the
Company and the Selling Stockholders and any Permitted Transferees participating
in such Requested Public Offering, and shall include, among other provisions,
indemnities to the effect and to the extent provided in Section 7. At the
request of the Company, any Selling Stockholder or Permitted

                                     - 15 -
<PAGE>
Transferee participating in the applicable Requested Public Offering shall be
parties to such underwriting agreements and the Selling Stockholders and any
Permitted Transferees participating in the applicable Requested Public Offering,
may, at their option, require that any or all of the representations and
warranties by, and the other agreements on the part of, the Company to and for
the benefit of such underwriters pursuant to such underwriting agreements also
be made to and for the benefit of the Selling Stockholders and the Permitted
Transferees participating in such Requested Public Offering and that any or all
of the conditions precedent to the obligations of such underwriters under such
underwriting agreements also be conditions precedent to the obligations of the
Selling Stockholders and the Permitted Transferees participating in such
Requested Public Offering. Notwithstanding anything to the contrary herein,
neither the Selling Stockholders nor any Permitted Transferees participating in
the applicable Requested Public Offering shall be required to make any
representations or warranties to or agreements with the Company or the
underwriters other than representations, warranties or agreements regarding such
Selling Stockholder or such Permitted Transferee, respectively, its ownership of
the Registrable Securities being offered on its behalf, its intended method of
distribution of such Registrable Securities and any other representation
required by law. In the case of a Requested Public Offering, immediately prior
to the signing of the applicable underwriting agreement, the Managing
Underwriter shall notify the Company, each Selling Stockholder and each
Permitted Transferee participating in such Requested Public Offering of the
price, underwriting discount and other financial terms at which it expects the
applicable Registrable Securities to be sold. The price, underwriting discount
and other financial terms related to the sale of the Registrable Securities in
the related underwriting agreement shall be subject to the reasonable approval
of each Selling Stockholder and each Permitted Transferee participating in such
Requested Public Offering. If one or more Selling Stockholders or Permitted
Transferees participating in such Requested Public Offering does not provide
such approval, the Registrable Securities of such non-approving Selling
Stockholders and Permitted Transferees shall not be included in such Requested
Public Offering and in such case if the Company had previously implemented a pro
rata reduction in the number of Registrable Securities that the Selling
Stockholders and Permitted Transferees providing such approval may sell in such
Requested Public Offering, the Company shall implement a corresponding pro rata
increase in the number of Registrable Securities that the Selling Stockholders
and Permitted Transferees providing such approval shall sell in such Requested
Public Offering.

            (b) Over-allotment Options. If and to the extent that (i) the
underwriting agreement executed in connection with a Requested Public Offering
as provided in Section 5(a) grants the applicable underwriters an over-allotment
option, (ii) the underwriters elect to exercise such over-allotment option and
(iii) the Selling Stockholders and/or any Permitted Transferees participating in
such Requested Public Offering at the time of such exercise(s) still hold
Registrable Securities, the Company, the Selling Stockholders and any Permitted
Transferees hereby agree that the obligations, if any, of the Company, the
Selling Stockholders and Permitted Transferees to sell additional Shares
pursuant to such over-allotment option shall be satisfied first from the
Registrable Securities still held by the Selling Stockholders and any Permitted
Transferees at the time of such exercise(s), with the remainder, if any, to be
covered by the Company.

            6. Lockup Agreements.


                                     - 16 -
<PAGE>
            (a) By the Selling Stockholders and Permitted Transferees. (i)
Notwithstanding anything in this Agreement to the contrary, during the SPCC
Sponsorship Period, the Selling Stockholders and the Permitted Transferees shall
not sell or transfer any Registrable Securities other than through a Requested
Public Offering sponsored by the Company and effected pursuant to this
Agreement; provided, however, that each of the Selling Stockholders shall be
permitted to dividend or otherwise transfer all or any portion of its Shares to
not more than a total of seven (7) permitted transferees (the "Permitted
Transferees") to be selected, in the case of Cerro or SPC, exclusively from
among Cerro's parent corporation, SPC, and Cerro's parent corporation's trust
shareholders and/or beneficiaries and any Person owned or controlled by such
trust shareholders and/or beneficiaries, and in the case of PDOCC or Climax,
exclusively from among the Affiliates of PDOCC and Climax; provided, further,
that, in advance of effecting any such dividend or transfer, the Selling
Stockholders shall provide written notice to the Company of the proposed
Permitted Transferee, notice information for the proposed Permitted Transferee,
the date of transfer and the number of Shares to be transferred; provided,
further, that any such Permitted Transferee shall first execute and deliver to
the Company one or more counterparts to this Agreement agreeing to be bound by
its terms.

            (ii) Notwithstanding anything in this Agreement to the contrary,
during the period beginning on the Effective Time and ending on the Termination
Date, none of the Selling Stockholders or the Permitted Transferees, if any,
shall, without the prior written consent of AMC and the Company, which consent
shall not be unreasonably withheld, knowingly sell all or any portion of its
shares of Common Stock to any strategic buyers or competitors of the Company
other than through a Public Offering effected pursuant to this Agreement.

            (iii) If and to the extent requested by the Managing Underwriter
(or, in the case of a non-Underwritten Public Offering, the Company), the
Selling Stockholders and any Permitted Transferees agree, to the extent that the
Selling Stockholders and such Permitted Transferees are timely notified by the
Managing Underwriter (or the Company), not to effect any public sale or
distribution (including a sale under Rule 144) of Registrable Securities, or any
securities convertible into or exchangeable or exercisable for such securities,
during the 10 days prior to and the 60 days after the consummation or
termination of such Public Offering or non-Underwritten Public Offering (or for
such longer period of time not to exceed 90 days as is sufficient and
appropriate, in the opinion of the Managing Underwriter (or, in the case of a
non-Underwritten Public Offering, the Company), in order to complete the sale
and distribution of the securities included in such Public Offering), except as
part of such Public Offering, whether or not the Selling Stockholders or such
Permitted Transferees participate in such Public Offering.

            (b) By the Company. (i) To the extent the Company is timely notified
by the Managing Underwriter, the Selling Stockholders or any Permitted
Transferee, the Company agrees and, to the extent requested by the Managing
Underwriter, shall use its reasonable best efforts to cause its executive
officers and directors to agree, not to effect any public sale or distribution
of the Company's equity securities, or any securities convertible into or
exchangeable or exercisable for such securities, during the 10 days prior to and
the 60 days after the consummation or termination of a Requested Public Offering
(or for such longer period of time not to exceed 90 days as is sufficient and
appropriate, in the opinion of the Managing Underwriter), except as part of such
underwritten registration and except pursuant to

                                     - 17 -
<PAGE>
registrations on Form S-4 or in connection with any employee benefit plan or
pursuant to the exercise of outstanding options, warrants or similar rights; and

            (ii) The Company agrees not to conduct during the SPCC Sponsorship
Period a primary offering of any equity securities or any securities convertible
into or exchangeable or exercisable for such securities; provided, however, that
the Company shall have the right during such period to issue shares of Common
Stock or equity securities or any securities convertible into or exchangeable
for such securities, including Common Stock issuable upon the sale or conversion
of the Class A Common Stock, in connection with acquisitions, mergers, business
combinations, benefit plans and other similar transactions, as the case may be.

            (c) By AMC. AMC agrees not to sell, and will use its reasonable best
efforts to prevent any of its Affiliates from selling, during the SPCC
Sponsorship Period any shares of Common Stock or other equity securities or any
securities convertible into or exchangeable or exercisable for such securities,
including Common Stock issuable upon the sale or conversion of the Class A
Common Stock.

            7. Indemnification.

            (a) Indemnification by the Company. The Company shall, to the full
extent permitted by law, indemnify and hold harmless each seller of Registrable
Securities included in the Shelf Registration Statement, its directors,
officers, employees, advisors and agents (collectively, "Representatives"), and
each other Person, if any, who controls any such seller within the meaning of
the Securities Act or the Exchange Act and each such controlling Person's
Representatives (collectively, the "Company Indemnitees"), against any losses,
claims, damages, expenses or liabilities, joint or several (together, "Losses"),
to which such Company Indemnitees may become subject under the Securities Act or
otherwise, insofar as such Losses (or actions or proceedings in respect thereof)
arise out of or are based upon any untrue statement or alleged untrue statement
of any material fact contained in the Shelf Registration Statement, any
preliminary prospectus, final prospectus or summary prospectus contained
therein, or any amendment or supplement thereto, including all documents
incorporated therein by reference, or any omission or alleged omission to state
therein a material fact required to be stated therein or necessary to make the
statements therein (in the case of a prospectus, in the light of the
circumstances under which they were made) not misleading and such untrue
statement or alleged untrue statement or omission or alleged omission was not
corrected in a subsequent amendment or supplement prior to or concurrently with
the sale of Registrable Securities to the Person asserting such Loss, and the
Company will reimburse such Company Indemnitees for any legal or any other
expenses reasonably incurred by them in connection with investigating or
defending any such Loss (or action or proceeding in respect thereof); provided
that the Company shall not be liable to a Company Indemnitee in any such case to
the extent that any such Loss (or action or proceeding in respect thereof)
arises out of or is based upon (x) an untrue statement or alleged untrue
statement or omission or alleged omission made in any such registration
statement, preliminary prospectus, final prospectus, summary prospectus,
amendment or supplement in reliance upon and in conformity with written
information furnished by the related seller to the Company expressly for use in
the preparation thereof or (y) such related seller's failure to send or give a
copy of the final prospectus to the Persons who assert an untrue statement or
alleged untrue statement or omission or alleged omission at or prior to the
written confirmation of the

                                     - 18 -
<PAGE>
sale of Registrable Securities to such Person if such statement or omission was
corrected in such final prospectus. The Company shall also indemnify each other
Person who participates (including as an underwriter) in the offering or sale of
Registrable Securities, their officers and directors and each other Person, if
any, who controls any such participating Person within the meaning of the
Securities Act or the Exchange Act to the same extent as provided above with
respect to Company Indemnitees. The indemnity in this paragraph (a) of Section 7
shall be in addition to any liability the Company may otherwise have.

            (b) Indemnification by the Sellers. Each holder of Registrable
Securities which are included or are to be included in the Shelf Registration
Statement, as a condition to including Registrable Securities in such
registration statement, shall, severally and not jointly, to the full extent
permitted by law, indemnify and hold harmless the Company, its Representatives,
and each other Person, if any, who controls the Company within the meaning of
the Securities Act or the Exchange Act and each such controlling Person's
Representatives (collectively, the "Seller Indemnitees") against any Losses to
which the Seller Indemnitees may become subject under the Securities Act or
otherwise, insofar as such Losses (or actions or proceedings in respect thereof)
arise out of or are based upon any untrue statement or alleged untrue statement
of any material fact contained in any such registration statement, any
preliminary prospectus, final prospectus or summary prospectus contained
therein, or any amendment or supplement thereto, or any omission or alleged
omission to state therein a material fact required to be stated therein or
necessary to make the statements therein (in the case of a prospectus, in the
light of the circumstances under which they were made) not misleading, if such
untrue statement or alleged untrue statement or omission or alleged omission was
made in reliance upon and in conformity with written information furnished to
the Company by such holder specifically stating that it is for use in the
preparation of such registration statement, preliminary prospectus, final
prospectus, summary prospectus, amendment or supplement and was not corrected in
a subsequent writing prior to or concurrently with the sale of Registrable
Securities to the Person asserting such Loss; provided, however, that the
aggregate amount which may be recovered from any holder of Registrable
Securities pursuant to the indemnification provided for in this Section 7(b) in
connection with any registration and sale of Registrable Securities shall be
limited to the total proceeds received by such holder from the sale of such
Registrable Securities. Such holders shall also indemnify each other Person who
participates (including as an underwriter) in the offering or sale of
Registrable Securities, their officers and directors and each other Person, if
any, who controls any such participating Person within the meaning of the
Securities Act or the Exchange Act to the same extent as provided above with
respect to the Seller Indemnitees. The indemnity in this paragraph (b) of
Section 7 shall be in addition to any liability such holder may otherwise have.

            (c) Notices of Claims, etc. Promptly after receipt by an Indemnified
Party of notice of the commencement of any action or proceeding involving a
claim referred to in the preceding paragraph (a) or (b) of this Section 7, such
Indemnified Party will, if a claim in respect thereof is to be made against an
Indemnifying Party pursuant to such paragraphs, give written notice to the
latter of the commencement of such action, provided that the failure of any
Indemnified Party to give notice as provided herein shall not relieve the
Indemnifying Party of its obligations under the preceding paragraphs of this
Section 7, except to the extent that the Indemnifying Party is actually
prejudiced by such failure to give notice. In case any such action is brought
against an Indemnified Party, the Indemnifying Party shall be entitled to
participate in

                                     - 19 -
<PAGE>
and to assume the defense thereof, jointly with any other Indemnifying Party
similarly notified to the extent that it may wish, with counsel reasonably
satisfactory to such Indemnified Party, and after notice from the Indemnifying
Party to such Indemnified Party of its election so to assume the defense
thereof, the Indemnifying Party shall not be liable to such Indemnified Party
for any legal or other expenses subsequently incurred by the latter in
connection with the defense thereof other than reasonable costs of
investigation; provided that the Indemnified Party or Indemnified Parties shall
have the right to employ one counsel to represent it or them if (A) in the
reasonable judgment of the Indemnified Party or Indemnified Parties, it is
advisable for it or them to be represented by separate counsel by reason of
having legal defenses which are different from or in addition to those available
to the Indemnifying Party or (B) the named parties to any such action include
both the Indemnifying Party and the Indemnified Party and the Indemnified Party
shall have been advised by its counsel that there may be a conflict of interest
between the Indemnified Party and the Indemnifying Party in the conduct of the
defense of such action, and in any of the foregoing events the reasonable fees
and expenses of such one counsel shall be paid by the Indemnifying Party. If the
Indemnifying Party is not entitled to, or elects not to, assume the defense of a
claim, it will not be obligated to pay the fees and expenses of more than one
counsel for the Indemnified Parties with respect to such claim, unless in the
reasonable judgment of any Indemnified Party a conflict of interest may exist
between such Indemnified Party and any other Indemnified Parties with respect to
such claim, in which event the Indemnifying Party shall be obligated to pay the
fees and expenses of such additional counsel for the Indemnified Parties or
counsels. No Indemnifying Party shall consent to entry of any judgment or enter
into any settlement without the consent of the Indemnified Party which (i) does
not include as an unconditional term thereof the giving by the claimant or
plaintiff to such Indemnified Party of a release from all liability in respect
to such claim or litigation or (ii) includes any admission of wrongdoing on the
part of the Indemnified Party.

            (d) Contribution. If the indemnity and reimbursement obligation
provided for in any paragraph of this Section 7 is unavailable or insufficient
to hold harmless an Indemnified Party in respect of any Losses (or actions or
proceedings in respect thereof) referred to therein, then the Indemnifying Party
shall contribute to the amount paid or payable by the Indemnified Party as a
result of such Losses (or actions or proceedings in respect thereof) in such
proportion as is appropriate to reflect the relative fault of the Indemnifying
Party on the one hand and the Indemnified Party on the other hand in connection
with untrue statements or alleged untrue statements or omissions or alleged
omissions which resulted in such Losses, as well as any other relevant equitable
considerations. The relative fault shall be determined by reference to, among
other things, whether the untrue or alleged untrue statement of a material fact
or the omission or alleged omission to state a material fact relates to
information supplied by the Indemnifying Party or the Indemnified Party and the
parties' relative intent, knowledge, access to information and opportunity to
correct or prevent such untrue statement or omission. The parties hereto agree
that it would not be just and equitable if contributions pursuant to this
paragraph were to be determined by pro rata allocation or by any other method of
allocation which does not take account of the equitable considerations referred
to in the first sentence of this paragraph. The amount paid by an Indemnified
Party as a result of the Losses referred to in the first sentence of this
paragraph shall be deemed to include any legal and other expenses reasonably
incurred by such Indemnified Party in connection with investigating or defending
any Loss which is the subject of this paragraph.


                                     - 20 -
<PAGE>
            No Indemnified Party guilty of fraudulent misrepresentation (within
the meaning of Section 11(f) of the Securities Act) shall be entitled to
contribution from the Indemnifying Party if the Indemnifying Party was not
guilty of such fraudulent misrepresentation.

            Notwithstanding the provisions of this Section 7(d), no Indemnifying
Party (other than the Company) shall be required to contribute any amount which
is in excess of the amount by which the total proceeds received by such
Indemnifying Party from the sale of Registrable Securities (net of all
underwriting discounts and commissions) exceeds the amount of any damages that
such Indemnifying Party has otherwise been required to pay by reason of such
untrue or alleged untrue statement or omission or alleged omission.

            (e) Other Indemnification. Indemnification similar to that specified
in the preceding paragraphs of this Section 7 (with appropriate modifications)
shall be given by the Company and each seller of Registrable Securities with
respect to any required registration or other qualification of securities under
any federal or state law or regulation of any governmental authority other than
the Securities Act.

            (f) Other Rights to Indemnification or Contribution. The provisions
of this Section 7 shall be in addition to any other rights to indemnification or
contribution which an Indemnified Party may have pursuant to law, equity,
contract or otherwise.

            8. Termination. This Agreement and the rights and obligations of the
parties hereto (other than Section 2(b), Section 3(g)(ii), Section 7 and this
Section 8, which shall survive any termination of this Agreement) shall
automatically terminate, and shall cease to be of any further force or effect on
the earlier of (i) the first day after the expiration of the Second Six-Month
Period and (ii) the date on which all of the Registrable Securities owned by the
Selling Stockholders and any Permitted Transferees on the date hereof have been
disposed of in accordance with the Shelf Registration Statement (such earlier
date, the "Termination Date"); provided, however, that in no event shall the
Termination Date be later than the date that is eighteen (18) months from the
date of this Agreement.

            9. Conditions to Obligations of Company and AMC. The parties to this
Agreement (including any Permitted Transferees) hereby agree that the
obligations of the Company and AMC under this Agreement are subject to the
condition that the Effective Time shall have occurred and, with respect to the
obligations of the Company and AMC under this Agreement to each Selling
Stockholder and Permitted Transferee, to the further conditions that each such
Selling Stockholder or Permitted Transferee, as the case may be, shall have
taken all steps required to be taken by it under Section 4.9(c) of the Restated
Certificate of Incorporation to effect the voluntary conversion of all shares of
Class A Common Stock owned by each such Selling Stockholder or Permitted
Transferee, as the case may be.

            10. Miscellaneous.

            (a) Notices. All notices, requests and other communications
hereunder must be in writing and will be deemed to have been duly given only if
delivered personally or by facsimile transmission or mailed (first class postage
prepaid) to the parties at the following addresses or facsimile numbers:


                                     - 21 -
<PAGE>
            If to Cerro or SPC, to:

                  Cerro Trading Company, Inc.
                  225 West Washington Street
                  Suite 1900
                  Chicago, Illinois  60606
                  Facsimile No.:  (312) 845-8769
                  email: robert.webb@marmon.com
                  Attn:  Robert W. Webb
                         Secretary

            with a copy to:

                  Cleary Gottlieb Steen & Hamilton LLP
                  2000 Pennsylvania Avenue, N.W.
                  Washington, D.C.  20006-1801
                  Facsimile No.:  (202) 974-1999
                  email: lsoldo@cgsh.com
                  Attn:  Linda J. Soldo

            If to PD, PDOCC or Climax, to it, in care of:

                  Phelps Dodge Corporation
                  One North Central Avenue
                  Phoenix, Arizona 85004
                  Facsimile No.:  (602) 366-7321
                  email: dcolton@phelpsdodge.com
                  Attn:  S. David Colton
                         Senior Vice President and General Counsel

            with a copy to:

                  Debevoise & Plimpton LLP
                  919 Third Avenue
                  New York, New York 10022
                  Facsimile No.:  (212) 909-6836
                  email: mwblair@debevoise.com
                  Attn:  Michael W. Blair


            If to the Company, to:

                  Southern Peru Copper Corporation
                  2575 East Camelback Road, Suite 500
                  Phoenix, Arizona  85016
                  Facsimile No.:  (602) 977-6700


                                     - 22 -
<PAGE>
                  email: armando.ortega@mm.gmexico.com
                  Attn:  Armando Ortega Gomez
                         Vice President-Legal Secretary

            with a copy to:

                  Milbank, Tweed, Hadley & McCloy LLP
                  One Chase Manhattan Plaza
                  New York, New York  10005
                  Facsimile No.:  (212) 530-5219
                  email: mfitzgerald@milbank.com
                  Attn:  Michael L. Fitzgerald

All such notices, requests and other communications will (i) if delivered
personally to the address as provided in this Section, be deemed given upon
delivery, (ii) if delivered by facsimile transmission to the facsimile number as
provided in this Section, be deemed given upon receipt, and (iii) if delivered
by mail in the manner described above to the address as provided in this Section
10(a), be deemed given upon receipt (in each case regardless of whether such
notice, request or other communication is received by any other Person to whom a
copy of such notice is to be delivered pursuant to this Section 10(a)). Any
party from time to time may change its address, facsimile number or other
information for the purpose of notices to that party by giving notice specifying
such change to the other parties hereto.

            (b) Entire Agreement. This Agreement sets forth the entire
understanding of the parties hereto with regard to the subject matter hereof and
supersedes all prior discussions and agreements between the parties with respect
to the subject matter hereof, including, without limitation, the Cerro Letter
Agreement and the PD Letter Agreement.

            (c) Amendment. This Agreement may be amended, supplemented or
modified only by a written instrument (which may be executed in any number of
counterparts) duly executed by or on behalf of each of the parties hereto.

            (d) Waiver. Subject to paragraph (e) of this Section 10, any term or
condition of this Agreement may be waived at any time by the party that is
entitled to the benefit thereof, but no such waiver shall be effective unless
set forth in a written instrument duly executed by or on behalf of the party
waiving such term or condition. No waiver by any party of any term or condition
of this Agreement, in any one or more instances, shall be deemed to be or
construed as a waiver of the same term or condition of this Agreement on any
future occasion.

            (e) Consents and Waivers. Any consent of a party hereto pursuant to
this Agreement, and any waiver by a party hereto of any provision of this
Agreement, shall be in writing (which may be executed in any number of
counterparts), and any such consent or waiver so given or taken will be binding
on such party.

            (f) Third Party Beneficiary. The terms and provisions of this
Agreement are intended solely for the benefit of each party hereto, their
respective successors or permitted assigns and any other holder of Registrable
Securities, and it is not the intention of the parties to

                                     - 23 -
<PAGE>
confer third-party beneficiary rights upon any other Person other than any
Person entitled to indemnity under Section 7.

            (g) Comparable Agreements. The Company hereby represents and
warrants to the Selling Stockholders that, as of the date hereof, it is not
party to any agreement with one or more third parties to effect the registration
under the Securities Act of all or part of any shares of Common Stock or Class A
Common Stock owned by such third parties on terms that are more favorable to
such third parties than the terms of this Agreement. Notwithstanding anything in
this Agreement to the contrary, the Company agrees with each of the Selling
Stockholders that, to the extent the Company agrees after the date hereof to
effect the registration under the Securities Act of all or part of any shares of
Common Stock owned by a third party, it shall only do so on terms that are
substantially identical to the terms of this Agreement.

            (h) Successors and Assigns. Cerro and SPC may assign their
respective rights and obligations under this Agreement solely to (w) Cerro's
parent corporation, (x) Persons who are trust shareholders and/or beneficiaries
of Cerro's parent corporation, (y) any Persons owned or controlled by such trust
shareholders and/or beneficiaries or (z) a transferee of greater than 50% of the
aggregate number of Registrable Securities owned by Cerro and SPC as of the date
hereof (such number to be adjusted proportionately to reflect any stock
dividend, stock split, reclassification, reorganization, recapitalization,
distribution or other similar event in respect of the Shares); provided that any
such assignee shall first execute one or more counterparts to this Agreement
agreeing to be bound by its terms. Climax and PDOCC may assign their respective
rights and obligations under this Agreement solely to (x) Persons who are
Affiliates of PDOCC and Climax or (y) a transferee of greater than 50% of the
aggregate number of Registrable Securities owned by Climax and PDOCC as of the
date hereof (such number to be adjusted proportionately to reflect any stock
dividend, stock split, reclassification, reorganization, recapitalization,
distribution or other similar event in respect of the Shares); provided that any
such assignee shall first execute one or more counterparts to this Agreement
agreeing to be bound by its terms. Except as expressly set forth above in this
Section 10(h), the rights and obligations of the Selling Stockholders and the
Permitted Transferees under this Agreement shall not be assignable. This
Agreement is binding upon, inures to the benefit of and is enforceable by the
parties hereto and their respective permitted successors and assigns.

            (i) Headings. The headings used in this Agreement have been inserted
for convenience of reference only and do not define or limit the provisions
hereof.

            (j) Invalid Provisions. If any provision of this Agreement is held
to be illegal, invalid or unenforceable under any present or future law, and if
the rights or obligations of any party hereto under this Agreement will not be
materially and adversely affected thereby, (i) such provision will be fully
severable, (ii) this Agreement will be construed and enforced as if such
illegal, invalid or unenforceable provision had never comprised a part hereof
and (iii) the remaining provisions of this Agreement will remain in full force
and effect and will not be affected by the illegal, invalid or unenforceable
provision or by its severance herefrom.

            (k) Remedies. Except as otherwise expressly provided for herein, no
remedy conferred by any of the specific provisions of this Agreement is intended
to be exclusive of any other remedy, and each and every remedy shall be
cumulative and shall be in addition to every

                                     - 24 -
<PAGE>
other remedy given hereunder or now or hereafter existing at law or in equity or
by statute or otherwise. The election of any one or more remedies by any party
hereto shall not constitute a waiver by any such party of the right to pursue
any other available remedies.

            Damages in the event of breach of this Agreement by a party hereto
or any other holder of Registrable Securities would be difficult, if not
impossible, to ascertain, and it is therefore agreed that each such Person, in
addition to and without limiting any other remedy or right it may have, will
have the right to an injunction or other equitable relief in any court of
competent jurisdiction, enjoining any such breach, and enforcing specifically
the terms and provisions hereof and the Company and each holder of Registrable
Securities, by its acquisition of such Registrable Securities, hereby waives any
and all defenses it may have on the ground of lack of jurisdiction or competence
of the court to grant such an injunction or other equitable relief. The
existence of this right will not preclude any such Person from pursuing any
other rights and remedies at law or in equity which such Person may have.

            (l) Governing Law. This Agreement shall be governed by and construed
in accordance with the laws of the State of New York.

            (m) Counterparts. This Agreement may be executed in any number of
counterparts, each of which will be deemed an original, but all of which
together will constitute one and the same instrument.



                                     - 25 -
<PAGE>
            IN WITNESS WHEREOF, this Agreement has been duly executed and
delivered by the duly authorized officer of each party hereto as of the date
first above written.

                                    CERRO TRADING COMPANY, INC.



                                    By: ______________________________________
                                        Name:
                                        Title:

                                    SPC INVESTORS, L.L.C.




                                    By: ______________________________________
                                        Name:
                                        Title:

                                    PHELPS DODGE CORPORATION
                                        solely with respect to Section 3(b)(ii),
                                        Section 3(e), Section 4(m) and Section 5
                                        of this Agreement



                                    By: ______________________________________
                                        Name:
                                        Title:

                                    PHELPS DODGE OVERSEAS CAPITAL CORPORATION



                                    By: ______________________________________
                                        Name:
                                        Title:

                                    CLIMAX MOLYBDENUM B.V.



                                    By: ______________________________________
                                        Name:
                                        Title:



                                     - 26 -
<PAGE>
                                    SOUTHERN PERU COPPER CORPORATION



                                    By: ______________________________________
                                        Name:
                                        Title:

                                    AMERICAS MINING CORPORATION
                                        solely with respect to Section 3(g)(ii)
                                        and Section 6(c) of this Agreement

                                    By: ______________________________________
                                        Name:
                                        Title:




                                     - 27 -
<PAGE>
                                                                      SCHEDULE I

                        OWNERSHIP OF CLASS A COMMON STOCK

<TABLE>
<CAPTION>
Selling Stockholders                        Number of Shares of Class A Common
                                            Stock Beneficially Owned
-----------------------------------------   ----------------------------------
<S>                                         <C>
Cerro Trading Company, Inc.                  9,498,088
SPC Investors, L.L.C.                        1,880,000
Phelps Dodge Overseas Capital Corporation    8,963,796
Climax Molybdenum B.V.                       2,210,000
TOTAL                                       22,551,884
</TABLE>
<PAGE>
                                                                       EXHIBIT A

                              PLAN OF DISTRIBUTION
             [TO BE INCLUDED IN THE SHELF REGISTRATION STATEMENT.]

            We have registered the __________ shares of our common stock offered
in this prospectus on behalf of the selling stockholders. The selling
stockholders will pay all reasonable and customary expenses of this
registration, including, among other things, reasonable and customary fees and
expenses of counsel or other advisors to the selling stockholders, reasonable
and customary fees and expenses of counsel for us and of our independent
registered public accounting firm and expenses that are incurred by us in
connection with arranging, preparing for and participating in, selling efforts.
The selling stockholders will be responsible for paying any commissions,
discounts, or other brokerage fees and any transfer taxes incurred in connection
with its sale of any of the shares.

            The shares of common stock may be sold in one or more transactions
at fixed prices, at prevailing market prices at the time of sale, at prices
related to the prevailing market prices, at varying prices determined at the
time of sale, or at negotiated prices. These sales may be effected at various
times in one or more of the following transactions, or in other kinds of
transactions:

            -     on the New York Stock Exchange, in the over-the-counter market
                  or on any other quotation system or exchange on which such
                  securities may be quoted or listed;

            -     in private transactions and transactions otherwise than on
                  these exchanges or systems or in the over-the-counter market;

            -     in connection with short sales of the shares;

            -     by pledge to secure debt and other obligations;

            -     through the writing of options, whether the options are listed
                  on an options exchange or otherwise;

            -     in connection with the writing of non-traded and
                  exchange-traded call options, in hedge transactions and in
                  settlement of other transactions in standardized or
                  over-the-counter options; or

            -     through a combination of any of the above transactions or any
                  other method permitted pursuant to applicable law.

            The shares of common stock may be offered to or through underwriters
or agents designated from time to time or to or through brokers or dealers, or
through any combination of these methods of sale. The methods by which the
shares of common stock may be sold include:
<PAGE>
            -     a block trade (which may involve crosses) in which the broker
                  or dealer will attempt to sell the shares of common stock as
                  agent but may position and resell a portion of the block as
                  principal to facilitate the transaction;


            -     purchases by a broker or dealer as principal and resale by
                  such broker or dealer for its own account pursuant to this
                  prospectus;


            -     exchange distributions or secondary distributions in
                  accordance with the rules of the NYSE;


            -     ordinary brokerage transactions and transactions in which the
                  broker solicits purchasers;


            -     privately negotiated transactions; and


            -     any other method permitted pursuant to applicable law.

            An underwriter, agent, broker or dealer may receive compensation in
the form of discounts, concessions or commissions from the selling stockholders
or the purchasers of the securities for whom such broker-dealers may act as
agents or to whom they sell as principals, or both (which compensation as to a
particular broker-dealer might be in excess of customary commissions). A member
firm of an exchange on which our securities are traded might be engaged to act
as a selling stockholder's agent in the sale of shares by such selling
stockholder.

            During the first six-month period following the effectiveness date
of the registration statement, which six-month period is subject to extension in
certain circumstances, the selling stockholders and their successors, including
their permitted transferees, pledgees or donees or their successors, may sell
the common stock only in underwritten offerings sponsored by us in an amount,
subject to the following sentence, determined by the managing underwriter to be
the maximum amount of shares owned by the selling stockholders that can be sold
without significant market disruption. Notwithstanding the foregoing, the number
of shares included in any such underwritten offering will not be less than
20,000,000, or such lesser amount as the managing underwriter determines can be
sold without significant market disruption. In either case, 20,000,000 or such
lesser amount of shares will be adjusted proportionately to reflect any stock
dividend, stock split, reclassification, reorganization, recapitalization,
distribution or other similar event in respect of the shares of common stock.

            Such sales of common stock in underwritten offerings will be made
through underwriters, who may receive compensation in the form of discounts or
commissions from the selling stockholders. During the six-month period following
the first six-month period, the selling stockholders and their successors,
including their permitted transferees, pledges or donees or their successors,
may sell common stock directly to purchasers in amounts not to exceed 2,000,000
shares in the aggregate per calendar month (such 2,000,000 to be adjusted

                                     - 2 -
<PAGE>
proportionately to reflect any stock dividend, stock split, reclassification,
reorganization, recapitalization, distribution or other similar event in respect
of the shares of common stock), but will not have a right to request
underwritten offerings sponsored by us.

            In addition to selling common stock under this prospectus, the
selling stockholders and their permitted transferees may, subject to the
restrictions set forth in the Registration Rights Agreement dated March 31,
2005, by and between us, Americas Mining Corporation, Cerro Trading Company,
Inc., SPC Investors, L.L.C., Phelps Dodge Corporation, Phelps Dodge Overseas
Capital Corporation and Climax Molybdenum B.V., sell their common stock pursuant
to Rule 144 under the Securities Act of 1933 or by any other legally available
means.

            We will agree in connection with underwritten offerings sponsored by
us to indemnify the selling stockholders against certain losses, claims,
damages, liabilities and expenses, including liabilities under the Securities
Act of 1933.

            The selling stockholders and any broker-dealers or agents that
participate with the selling stockholders in the sale of shares may be
"underwriters" within the meaning of the Securities Act of 1933. Any commissions
received by broker-dealers or agents on the sales and any profit on the resale
of shares purchased by broker-dealers or agents may be deemed to be underwriting
commissions or discounts under the Securities Act of 1933.

            The selling stockholders and any broker-dealers or agents that
participate with the selling stockholders in the sale of shares may be subject
to the Exchange Act and the rules and regulations thereunder. The Exchange Act
rules include, without limitation, Regulation M, which may limit the timing of
purchase and sales of any of the securities by the selling stockholders and any
other such person. In addition, Regulation M of the Exchange Act may restrict
the ability of any person participating in the distribution to engage in
market-making activities with respect to the shares being distributed for a
period of up to five business days before the commencement of such distribution.
This may affect the marketability of the securities.

            Because the selling stockholders may be deemed to be underwriters,
the selling stockholders must deliver this prospectus in the manner required by
the Securities Act of 1933.

                                      * * *



                                      - 3 -
<PAGE>
                                                                       EXHIBIT B

                            FORM OF RESTRICTED LEGEND

THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER
THE UNITED STATES SECURITIES ACT OF 1933.

THE SHARES OF COMMON STOCK REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO
PROVISIONS CONTAINED IN THE REGISTRATION RIGHTS AGREEMENT DATED MARCH 31, 2005,
BY AND BETWEEN SOUTHERN PERU COPPER CORPORATION, AMERICAS MINING CORPORATION,
CERRO TRADING COMPANY, INC., SPC INVESTORS, L.L.C., PHELPS DODGE CORPORATION,
PHELPS DODGE OVERSEAS CAPITAL CORPORATION AND CLIMAX MOLYBDENUM B.V., COPIES OF
WHICH ARE ON FILE IN THE OFFICE OF THE SECRETARY OF SOUTHERN PERU COPPER
CORPORATION.
<PAGE>
                                                                     EXHIBIT C-1

                                 FORM OF OPINION

                                       OF

                              CERRO SPECIAL COUNSEL




                                             [date]


Southern Peru Copper Corporation
[address]

            Re:   Cerro Trading Company, Inc.

Ladies and Gentlemen:

            We have been requested by our client, Cerro Trading Company, Inc., a
Delaware corporation ("Cerro"), to furnish you our opinion regarding the
eligibility for sale under Rule 144(k) under the U.S. Securities Act of 1933, as
amended (the "Securities Act"), of ________ shares (the "Shares") of the common
stock, par value $0.01 per share, of Southern Peru Copper Corporation, a
Delaware corporation ("SPCC").

            In arriving at the opinion expressed below, we have reviewed the
following documents:

            (i) a letter furnished by Cerro to us dated [date], a copy of which
            is attached as Exhibit A, and

            (ii) facsimile copies of the certificates held by Cerro evidencing
            the Shares attached as Exhibit B, each of which bears a restrictive
            legend referring to limitations on transfer under the Securities Act
            (the "Restrictive Legends").

            In addition, we have made such investigations of law as we have
deemed appropriate as a basis for the opinion expressed below.

            In rendering the opinion expressed below, we have assumed the
authenticity of all documents submitted to us as originals and the conformity to
the originals of all documents submitted to us as copies. In addition, we have
assumed and have not verified the accuracy as to factual matters of each
document we have reviewed.
<PAGE>
            Based on the foregoing, it is our opinion that the Shares meet the
requirements of Rule 144(k) and that the certificates evidencing the Shares may
be issued without the Restrictive Legends.

            The foregoing opinion is limited to the federal securities law of
the United States of America.

            We are furnishing this opinion letter to you solely for your benefit
in connection with your consideration of the delegending of the Shares held by
Cerro. This opinion letter is not to be relied upon by or furnished to any other
person or used, circulated, quoted or otherwise referred to for any other
purpose, except that a copy of this letter may be furnished to, and relied on
by, SPCC's transfer agent in connection with its delegending the Shares. We
assume no obligation to advise you or any other person, or to make any
investigations, as to any legal developments or factual matters arising
subsequent to the date hereof that might affect the opinions expressed herein.

                                   Very truly yours,

                                   [Cerro's special counsel]



                                   By:_______________________________________
                                             ______________, a Partner

Enclosures



                                     - 2 -
<PAGE>
                                                                     EXHIBIT C-2

                                 FORM OF OPINION

                                       OF

                               PD SPECIAL COUNSEL




                                                               ___________, 2005

Southern Peru Copper Corporation
2575 East Camelback Road, Suite 500
Phoenix, Arizona  85016
Facsimile No.:  (602) 977-6700
email: armando.ortega@mm.gmexico.com
Attn:  Armando Ortega Gomez
       Vice President-Legal Secretary

Ladies and Gentlemen:

            We have acted as special counsel to Phelps Dodge Corporation
("Phelps Dodge"), Phelps Dodge Overseas Capital Corporation ("PDOCC") and Climax
Molybdenum B.V. ("Climax") (collectively, the "PD Entities"), in connection with
the exchange or transfer by PDOCC and Climax of 8,963,796 and 2,210,000 shares
(collectively, the "Shares"), respectively, of Common Stock, par value $.01 per
share (the "Common Stock"), of Southern Peru Copper Corporation ("SPCC"), a
Delaware corporation.

            PDOCC is a founding stockholder of SPCC and acquired 11,173,796
shares of Class A Common Stock on January 2, 1996. On December 17, 2004, PDOCC
transferred 2,210,000 shares of Class A Common Stock of SPCC to Phelps Dodge as
a dividend. Through a series of capital contributions and an inter-company
transfer in exchange for a note, the 2,210,000 shares of Class A Common Stock of
SPCC were subsequently transferred to Climax on December 22, 2004. As of [   ],
2005, PDOCC and Climax held 11,173,796 shares of Class A Common Stock, par value
$.01 per share (the "Class A Common Stock"), of SPCC, which comprised 13.96% of
the outstanding capital stock of SPCC. Their ownership of Class A Common Stock
gave the PD Entities certain rights with respect to the management of SPCC.
Pursuant to an Agreement Among Certain Stockholders of Southern Peru Copper
Corporation, dated as of January 2, 1996, entered into by and between SPCC,
Southern Peru Limited, ASARCO Incorporated, Cerro Trading Company, Inc. and
PDOCC, as amended (the "Stockholders Agreement"), the PD Entities had the right
to nominate two of the 15 members of

                                     - 3 -
<PAGE>
the board of directors of SPCC. In addition, under SPCC's by-laws, PDOCC, as a
shareholder holding 10 percent or more of the Class A Common Stock, had the
right to call special meetings of SPCC stockholders.

            On January 29, 2004, the two directors appointed by the PD Entities
to the SPCC Board resigned. The PD Entities have not nominated any replacements
since that time.

            On December 22, 2004, Phelps Dodge entered into a Letter Agreement
with Americas Mining Corporation ("AMC") in which Phelps Dodge expressed its
intent to take all action reasonably necessary to convert the Class A Common
Stock of PDOCC and Climax into Common Stock upon the closing of a strategic
transaction (the "Transaction") involving Minera Mexico, S.A. de C.V. ("MM") and
SPCC. The Transaction involved MM becoming a subsidiary of SPCC in consideration
for the issuance of Common Stock by SPCC to AMC for its approximately 99% MM
ownership stake.

            On [   ], 2005, the Transaction was consummated. All of the Class A
Common Stock of SPCC owned by PDOCC and Climax has been converted into Common
Stock of SPCC. In addition, 67,207,640 shares of Common Stock were issued to AMC
as consideration in the transaction.

            As a result of these events, PDOCC and Climax collectively own
11,173,796 shares of Common Stock of SPCC. PDOCC owns 8,963,796 shares of Common
Stock, while Climax owns 2,210,000 shares of Common Stock. Due to the issuance
of the additional Common Stock in the Transaction, the collective holdings of
PDOCC and Climax constitute 7.59% of the outstanding capital stock of SPCC. Upon
conversion of the Class A Common Stock, the rights of the PD Entities under the
Stockholders Agreement, including their right to appoint two directors of SPCC,
were terminated. In addition, because PDOCC is no longer the holder of 10% of
the Class A Common Stock or 10% of the Common Stock, it no longer has the right
to call special meetings of SPCC stockholders.

            Three months have passed since the consummation of the Transaction
and the conversion of the Class A Common Stock owned by PDOCC and Climax into
Common Stock.

            In connection with this opinion, we have examined originals or
certified, conformed or reproduction copies of such agreements, instruments,
documents and records of the PD Entities, such certificates of public officials,
and such other documents, and have made such investigations of law, as we have
deemed necessary or appropriate for the purposes of this opinion. In all such
examinations, we have assumed the legal capacity of all natural persons
executing documents, the genuineness of all signatures on original or certified
copies, the authenticity of all original or certified copies and the conformity
to original or certified documents of all copies submitted to us as conformed or
reproduction copies. We have relied as to factual matters upon, and assume the
accuracy of, the statements made in the certificates of officers of the PD
Entities delivered to us and certificates and other statements or information of
or from public officials and officers and representatives of the PD Entities and
others.

                                     - 4 -
<PAGE>
            Based upon and subject to the foregoing, we are of the opinion that
the Shares are eligible for sale under Rule 144(k) under the Securities Act of
1933, as amended, and the certificates representing the Shares need not contain
any restricted legend at this time.

            This opinion is rendered to you in connection with the exchange or
transfer of shares of Common Stock of SPCC and may not be reproduced, referred
to or shown to or relied upon by any other person.

                                Very truly yours




                                     - 5 -