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                             STOCKHOLDERS AGREEMENT

          STOCKHOLDERS AGREEMENT, dated as of January 30, 1998, by and among 
Refraco Inc., a Delaware  corporation (the  "Company"),  The Alpine Group,  
Inc.,  a Delaware  corporation  ("Alpine"),  Minerals  Trading,  Inc., a 
Delaware corporation  ("MTI"), and Ralph Feuerring,  Charles Gehret, John 
Gehret and Stanley Weiss  (collectively,  the "Individual  Refraco  
Stockholders"  and, together with Alpine and MTI, the "Stockholders").

                             W I T N E S S E T H :

          WHEREAS,   concurrently  with  the  execution  and  delivery  of  
this Agreement,  the Company is acquiring American Premier Holdings, Inc., a 
Delaware corporation  ("APHI"),  through the  statutory  merger of APHI with 
and into the Company  (the  "Merger"),  pursuant  to  which  MTI and the  
Individual  Refraco Stockholders (collectively, the "Minority Stockholders") 
are acquiring shares of Class B common stock, par value $.01 per share (the 
"Class B Common Stock"),  of the Company  upon the terms and  conditions  set 
forth in the merger  agreement, dated as of January 18, 1998,  by and among  
Alpine,  the Company,  APHI and the Minority Stockholders the "Merger 
Agreement"); and

          WHEREAS,   Alpine,  which  currently  holds  all  of  the  issued  
and outstanding  shares of common  stock,  par value $.01 per share  (the  
"Ordinary Common Stock" and,  together with the Class B Common Stock, the 
"Common Stock"), of the  Company,  and the  Minority

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Stockholders desire to enter into this Stockholders Agreement for the purpose 
of regulating certain aspects of their relationship as stockholders of the 
Company; and

          WHEREAS, it is in the best interests of the Company and the 
Stockholders that such aspects of their relationship be so regulated;

          NOW,  THEREFORE,  in  consideration  of  the  foregoing,   the  
mutual covenants  and  agreements  contained  herein  and for other  good and 
 valuable consideration, the receipt and sufficiency of which are hereby 
acknowledged, the parties agree as follows:

          Section 1. DEFINITIONS. As used in this Agreement, the following 
terms shall have the  following  respective  meanings  (such  meanings  being 
 equally applicable to both the singular and plural form of the terms 
defined).

          "Affiliate"of  a Person  means a Person that  directly or  
indirectly, through one or more  intermediaries,  controls,  is  controlled  
by, or is under common control with, the first mentioned Person.

         "Agreement"   means  this   Stockholders   Agreement,   including  
all amendments,  modifications and supplements  hereto and any exhibits or 
schedules to any of the foregoing, and shall refer to this Agreement as the 
same may be in force and effect at the time such reference becomes operative.

         "By-Laws" means the By-Laws of the Company, as the same may be in 
force  and effect as of the date hereof.
 
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         "Certificate of Incorporation" means the Certificate of 
Incorporation of the Company, as the same may be in force and effect as of 
the date hereof.

         "Closing" means the closing of the Merger, which shall occur on the 
date hereof.

         "Convertible  Securities" means any evidences of indebtedness,  
shares (other than Common Stock) or other  securities  convertible into or 
exchangeable for Common Stock.

         "Governmental  Authority"  means any  nation or  government,  any 
state or other political subdivision thereof and any Person exercising 
executive, legislative, judicial, regulatory or administrative functions of 
or pertaining to government.

         "Person"means an individual, corporation, partnership, association, 
trust or any unincorporated organization.

         "Put Right"  means the right of each of the Minority  Stockholders 
to elect to sell to the Company shares of Class B Common Stock on the terms 
and conditions set forth in the Certificate of Incorporation.

         "Registration Rights Agreement" means that certain agreement, dated 
as of the date hereof, by and among the Company, Alpine and the Minority 
Stockholders pursuant to which the Company grants the Minority Stockholders 
certain registration rights.

         "Rule 144 Sales"  means open market  sales  pursuant to Rule 144 
under the Securities Act (or any successor rule or regulation).

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          "Securities Act" means the Securities Act of 1933, as
amended.

          Section 2.     Certain Agreements.

          2.1 Board of Directors. Each Stockholder shall vote (or shall cause 
to be voted) all of the shares of Common Stock owned or controlled by such 
Stockholder (including any shares of Common Stock hereafter acquired), at any 
regular or special meeting of stockholders of the Company, shall take all 
action by written consent in lieu of such meeting of stockholders, and shall 
take all other actions necessary, to ensure:

               (a) that the Board of Directors of the Company  shall  consist 
of such number of directors as may be determined by Alpine in its sole 
discretion (which number shall be greater than or equal to 10 so long as 
Alpine owns at least 80% of the outstanding Common Stock and the Minority 
Stockholders have their rights to designate board members hereunder); and

               (b) that  there  shall be  elected  as  members  of the  Board 
of Directors:

                    (i)  one individual designated by MTI;

                    (ii) one  individual  designated by the  Individual  
Refraco Stockholders collectively, as determined by the vote or consent of 
the Individual Refraco Stockholders holding a majority of the Common Stock 
held in the aggregate by all of the Individual Refraco Stockholders; and

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                    (iii)  the  individuals  designated  by  Alpine  to fill 
the remaining directorships.

          2.2 Removal.  Any or all of the  directors may be removed at any 
time, either with or without cause, by the affirmative vote or action by 
written consent of holders of a majority of the then outstanding Common Stock 
in accordance with the By-Laws; provided, however, that any director 
designated by MTI pursuant to the provisions of Section 2.1(b)(i) and any 
director designated by the Individual Refraco Stockholders collectively 
pursuant to the provisions of Section 2.1(b)(ii) may be removed at such time 
and in such manner only with cause and otherwise may be removed only by the 
party that designated such director.

          2.3 Vacancies.  In the event that a vacancy is created on the Board 
of Directors of the Company by the death, disability, retirement, resignation 
or removal (with or without cause) of a director, or otherwise there shall 
exist or occur any vacancy on the Board of Directors of the Company, each 
Stockholder hereby agrees to use its or his best efforts to cause the 
remaining directors to vote or take action by written consent, in accordance 
with the By-Laws, for the election of a nominee to be designated by the 
entity or group which had designated or was entitled to designate the 
director whose position has become vacant, provided that such designee was 
not previously a director of the Company or any of its Affiliates who was 
removed for cause from the Board of Directors of the Company or any of its 
Affiliates.

          2.4 No Proxies. Each Stockholder covenants and agrees that, except 
(i) as a result of transfers expressly permitted by, and pursuant to and in 
accordance with, this 
 
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Agreement and (ii) as otherwise provided in the last sentence of Section 2.5 
hereof, such Stockholder will have sole voting power with respect to such 
Stockholder's Common Stock and will not grant any proxy with respect to such 
Common Stock, enter into any voting trust or other voting agreement or 
arrangement with respect to such Common Stock or grant any other rights to 
vote such Common Stock other than the agreement to vote such Common Stock set 
forth herein.

          2.5 Further Assurances. In order to effectuate the provisions of 
this

Section 2, the Stockholders hereby agree that when any action or vote is 
required to be taken by such Stockholders pursuant to this Agreement, such 
Stockholders shall use their respective best efforts to call, or cause the 
appropriate officers and directors of the Company to call, a special or 
annual meeting of stockholders of the Company, as the case may be, or execute 
or cause to be executed a consent in writing in lieu of any such meetings in 
accordance with the General Corporation Law of the State of Delaware, to 
effectuate such action. In addition, if any Stockholder shall fail to vote as 
required by the specific terms of this Section 2, such Stockholder shall be 
deemed to have irrevocably constituted and appointed the other Stockholders 
as his proxy coupled with an interest to vote such Stockholder's Common Stock 
on a pro rata basis in accordance with the terms of this Section 2.

          2.6 Affiliate  Transactions.  During the term of this  Agreement,  
(a) Alpine will  continue to provide to Refraco the same level of staff  
support for corporate and  administrative  services that is currently being  
provided,  on a basis  consistent  with past  practice  using  existing  
staff and  replacements thereof,  but there  shall be no charge by  Alpine  
to  Refraco  for such  staff support (other than for  out-of-pocket  costs 
reasonably  incurred in connection therewith  and 

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the cost for employees of Alpine who devote substantially all their business 
time to Refraco) and (b) neither Alpine nor any of its Affiliates (other than 
any of Refaco's Subsidiaries) shall enter into any agreement or arrangement 
with Refraco or any of its Subsidiaries other than as contemplated by this 
Agreement, except for agreements or arrangements on an arm's length basis at 
rates or charges to Refraco or its Subsidiaries that are not less favorable 
than could be obtained by them from an unrelated third party. In connection 
with the administration of any insurance maintained by Alpine both for 
Refraco and for Alpine and other Subsidiaries of Alpine, Alpine shall submit 
and prosecute claims and otherwise provide such administration in a fair and 
equitable manner and shall not intentionally take any action in connection 
therewith that would give a preference or advantage to Alpine or to one 
Subsidiary over another under circumstances when Alpine has the ability to 
act in an manner that would not provide such a preference or advantage. 
Alpine shall purchase excess general liability insurance in the amount of $10 
million for the benefit of Refraco.

          Section 3.     Restrictions on Transfer of Shares of the Company.

          3.1  Transfer Restricted.

               3.1.1 No Common Stock,  or any interest  therein,  shall be 
sold, assigned, transferred,  pledged or otherwise encumbered or disposed of, 
directly or indirectly,  except in accordance with the provisions of this 
Agreement or as required by  applicable  law. The Company  shall not transfer 
upon its books and records any shares of Common Stock  purported to be 
transferred to any Person in violation of this Agreement.

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               3.1.2 In addition to each other restriction on transfer 
contained in this  Agreement,  except  for Rule 144  Sales,  a sale of  
shares in a public offering  and a transfer to the  Company,  no  Stockholder 
 shall sell,  assign, transfer,  pledge or otherwise encumber or dispose of 
any shares of Common Stock or any interest  therein to any Person  
(regardless  of the manner in which such Stockholder  initially acquired such 
Common Stock),  unless (a) the certificates representing  the  shares  issued 
to the  transferee  bear  appropriate  legends reflecting   the   
restrictions   on  transfer   contained  in  this   Agreement substantially 
to the following effect:

          "THE  SHARES  REPRESENTED  BY  THIS  CERTIFICATE  ARE  SUBJECT  TO 
          THE PROVISIONS OF A STOCKHOLDERS AGREEMENT DATED AS OF JANUARY 30, 
          1998 (A COPY OF WHICH IS ON FILE WITH THE  SECRETARY  OF THE  
          COMPANY) AND MAY NOT BE SOLD, TRANSFERRED, ASSIGNED, PLEDGED, 
          HYPOTHECATED OR OTHERWISE DISPOSED  OF  EXCEPT  IN  COMPLIANCE   
          WITH  THE  PROVISIONS  OF  SUCH STOCKHOLDERS AGREEMENT."

and (b) the transferee shall have executed and delivered to the Company, as a 
condition to its acquisition of the Common Stock, an appropriate document 
confirming that such transferee takes such shares subject to all the terms 
and conditions of this Agreement.

               3.1.3 In addition to each other restriction on transfer 
contained in this Agreement, no Stockholder shall sell, assign, transfer, 
pledge or otherwise encumber or dispose of any shares of Common Stock, or any 
interest therein, to any Person unless such sale, assignment, transfer, 
pledge or other encumbrance or disposition is pursuant to an effective 
registration statement under the Securities Act and under applicable state 
securities laws or an exemption from such registration is available.
                 
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               3.1.4 The  restrictions  on transfer  contained in this 
Agreement are in addition to, and not in limitation of, each other 
restriction on transfer contained in the Merger Agreement.

          3.2  Certain  Permitted  Transfers.  Notwithstanding  anything in 
this Agreement to the  contrary,  the  restrictions  contained in Section 3.3 
of this Agreement  shall not apply to the transfers of Common Stock described 
in clauses (a), (b) and (c) below and the  restrictions  contained in 
Sections 3.4, 3.5 and 3.6 of this Agreement  shall not apply to transfers of 
Common Stock described in any of the following clauses:

          (a)  any transfer to a legal representative in the
     event any Stockholder who is an individual becomes mentally
     incompetent;

          (b) any transfer by Alpine to a corporation or other entity that 
     owns, directly or indirectly,  100% of the equity of Alpine (an "Alpine  
     Parent") or to any wholly-owned  direct or indirect subsidiary of such 
     Alpine Parent (an "Alpine  Controlled  Subsidiary"),  it being 
     understood with respect to such  Alpine  Controlled  Subsidiary  that 
     the later sale,  liquidation  or spin-off of such Alpine Controlled 
     Subsidiary or other transaction in which the Alpine Parent ceases to 
     control,  directly or  indirectly,  100% of the equity of the Alpine  
     Controlled  Subsidiary  would  constitute an indirect sale of Common 
     Stock,  which sale may only be made in  compliance  with the terms and 
     restrictions set forth in this Agreement;

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          (c) any pledge by Alpine of the shares of Common  Stock owned by it 
     to any  lender or trustee  under any credit agreements or indentures 
     with respect to borrowed money of Alpine or the Company;

          (d) any transfer  without  consideration  by a  Stockholder  who is 
     an individual  to the  spouse  or issue of such  Stockholder  or to a 
     trust of which there are no principal  beneficiaries  other than such 
     Stockholder or the spouse or issue of such Stockholder;

          (e) any  transfer  by a  Stockholder  that is not an  individual  
     to a corporation or other entity that owns, directly or indirectly,  
     100% of the equity  of such  entity  (a  "Parent")  or to any  
     wholly-owned  direct  or indirect  subsidiary of such Parent (a 
     "Controlled  Subsidiary"),  it being understood with respect to such 
     Controlled  Subsidiary that the later sale, liquidation or spin-off of 
     such Controlled  Subsidiary or other transaction in which the Parent 
     ceases to control, directly or indirectly,  100% of the equity of the 
     Controlled  Subsidiary  would  constitute an indirect sale of Common 
     Stock,  which sale may only be made in compliance with the terms and 
     restrictions set forth in this Agreement;

          (f)  any transfer between Stockholders; or

          (g)  any transfer by a Stockholder to the Company pursuant to any 
     agreement between the Company and such Stockholder;
                              
provided that in the cases of (a) through (f), each transferee agrees in 
writing to take such Common Stock subject to, and to comply with,  the  
restrictions  on transfer contained in this

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Agreement.  In addition,  none of the restrictions on transfers of Common 
Stock  contained in this Agreement shall apply to a transfer by a Stockholder 
who is an individual upon his death,  by will, by the laws of descent or by 
operation of law, except that any such transfer  shall be subject to the  
requirements of Section 3.1.2 of this Agreement.  Any transfer of Common 
Stock  pursuant to and in compliance  with this Section 3.2 shall be a 
permitted transfer  under this  Agreement,  and any transferee of Common 
Stock pursuant to and in  compliance  with this  Section  3.2 (other  than 
the  Company) is herein referred to as a  "Permitted  Transferee."  Each  
Permitted  Transferee,  if not previously a Minority Stockholder,  shall, 
upon consummation of the transfer, be deemed a Minority Stockholder for 
purposes of this Agreement.

          3.3  Holding Periods.

               3.3.1  Each  Minority   Stockholder  shall  not  sell,  
exchange, distribute or otherwise dispose of, or reduce the risk of loss by 
short sale or otherwise with respect to, any of its or his shares of Common 
Stock, or enter into any contract or arrangement with respect to any of the 
foregoing matters, during the period commencing on the date of the Closing 
and ending on the thirty-third monthly anniversary thereof, except (i) for 
transfers described in Section 3.2(a) of this Agreement or the third from 
last sentence of Section 3.2 of this Agreement, (ii) pursuant to Section 3.5 
or 3.6 of this Agreement, (iii) pursuant to the terms of the Registration 
Rights Agreement, (iv) pursuant to the terms of the Guaranty (as defined in 
the Merger Agreement), (v) pursuant to the exercise of the Put Right 
following acceleration, if any, of such right as provided in the Certificate 
of Incorporation, or (vi) by reason of a transaction described in clause (z) 
of Section 3.3.2.

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               3.3.2 Except for  transfers  permitted  under Section 3.2 of 
this Agreement, Alpine agrees that it will not, and will not enter into any 
contract or agreement or adopt any resolution to (a) sell, exchange, 
distribute or otherwise dispose of, or reduce the risk of loss by short sale 
or otherwise with respect to, any of its equity interest in the Company or 
the capital stock of American Premier Inc., APHI's wholly-owned subsidiary 
("API"), or enter into any contract or arrangement with respect to any of the 
foregoing matters, or (b) cause or permit the Company to liquidate or to 
sell, exchange, distribute or otherwise dispose of any of the assets of API 
(other than in the ordinary course of its business and except for transfers 
to a wholly-owned subsidiary of the Company) during the period commencing on 
the date hereof and ending on the second anniversary of the date hereof; 
provided, however, that nothing herein will prevent Alpine from (x) 
responding to, negotiating with respect to or completing a transaction 
resulting from, an unsolicited offer received prior to that time which the 
Board of Directors of Alpine determines is necessary in order to comply with 
its fiduciary obligations to Alpine's public shareholders, (y) causing the 
merger of API, API Technologies and Adience, or (z) causing the acquisition 
of the Company in a transaction that qualifies as a reorganization within the 
meaning of Section 368(a)(1) of the Internal Revenue Code of 1986, as amended 
(the "Code"), in which the shareholders of the Company receive solely stock 
of the acquiring corporation as consideration for their capital stock of the 
Company and that does not affect the treatment for tax purposes of the 
Split-Off as a tax free distribution to MTI under Section 355(a) of the Code 
and the Merger as an "A" reorganization under Section 368(a)(1)(A) of the 
Code.

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          3.4  First  Offer  Rights.  The  Minority  Stockholders  may  sell  
or otherwise transfer Common Stock only in compliance with the provisions of 
this Section 3.4 and Section 3.3.1 of this Agreement, except for sales and 
transfers permitted by the exceptions to Section 3.3.1.

               3.4.1 Any  Minority  Stockholder  desiring  to sell or  
otherwise transfer Common Stock in compliance with this Section 3.4 (a 
"Selling Stockholder") shall first deliver written notice to Alpine, the 
Company and the other Minority Stockholders (the "Notice of Offer"), which 
Notice of Offer shall specify: (i) the number of shares of Common Stock owned 
by the Selling Stockholder which such Selling Stockholder wishes to sell (the 
"Offered Shares"); (ii) the proposed cash purchase price per share of the 
Offered Shares (the "Offer Price"); and (iii) the name of the prospective 
purchaser and all other material terms and conditions of the offer. The 
Notice of Offer shall constitute an irrevocable offer by the Selling 
Stockholder to sell to the other Stockholders the Offered Shares at the Offer 
Price, as hereinafter provided.

               3.4.2  Within 15 days  following  their  receipt of the Notice 
of Offer, each of the Minority Stockholders other than the Selling 
Stockholder (the "Retaining Stockholders") shall notify the Company, Alpine, 
the Selling Stockholder and the other Minority Stockholders in writing as to 
the number of Offered Shares, if any, up to his or its pro rata portion of 
the Offered Shares (based on the number of shares of Common Stock owned by 
such Retaining Stockholder compared to the number of shares of Common Stock 
owned by all Retaining Stockholders), that it or he is electing to purchase 
(such notification is hereinafter referred to as the "Stockholder's 
Acceptance" and each Retaining Stockholder electing to purchase Offered 

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Shares is hereinafter referred to as an "Accepting Stockholder"). If any 
Retaining Stockholder does not provide a Stockholder's Acceptance to the 
Company, Alpine, the Selling Stockholder and the other Minority Stockholders 
within such 15-day period, such Retaining Stockholder shall be deemed to have 
declined to purchase any of the Offered Shares. A Stockholder's Acceptance 
shall be deemed to be an irrevocable commitment to purchase at the Offer 
Price from the Selling Stockholder the number of Offered Shares which such 
Accepting Stockholder has elected to purchase pursuant to its or his 
Stockholder's Acceptance.

               3.4.3 If any Retaining Stockholder fails to exercise his right 
to purchase his full pro rata portion of the Offered Shares, each of the 
Accepting Stockholders who has exercised his right to purchase his full pro 
rata portion of the Offered Shares shall have an additional five days after 
the expiration of such 15-day period in which to give to the Selling 
Stockholder and to the other Accepting Stockholders who have exercised their 
right to purchase their full pro rata portion of the Offered Shares further 
notice (the "Further Notice") of his election to purchase all or a part of 
the Offered Shares that the Retaining Stockholders have not theretofore 
elected to purchase (the "Remaining Shares"). Each Further Notice shall state 
the number of additional shares which the Stockholder giving the Further 
Notice elects to purchase. The Remaining Shares shall be apportioned among 
those Stockholders who have given a Further Notice as follows:

          (a) Each  Stockholder  who has given a Further  Notice and who has 
          not yet been  apportioned  that number of additional  shares that 
          he elected to purchase in his Further  Notice (a  "Participating  
          Stockholder")  shall be apportioned  the lesser of (i) that  number 

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      of additional shares that he elected to purchase in his Further Notice 
      and which he has not yet been apportioned pursuant to this Section 
      3.4.3(a) or (ii) his Pro Rata Portion of the Unpurchased Shares, 
      whichever is lesser.

          (b) If the  apportionment  in Section  3.4.3(a) is followed  and 
     there remain at least one Participating  Stockholder and any Unpurchased 
      Shares, the procedure described in Section 3.4.3(a) shall be repeated.

          (c) For purposes of this Section 3.4.3,  "Unpurchased Shares" shall 
     be the Remaining  Shares that have not yet been  apportioned to 
     Participating Stockholders pursuant to Section 3.4.3(a), and a 
     Participating Stockholder's  "Pro Rata  Portion" of the Unpurchased  
     Shares shall be the number of  Unpurchased  Shares multiplied by the 
     fraction determined  by dividing the  number of shares of  Common Stock 
     that such Participating Stockholder held on the date the Company 
     received the Notice of Offer by the  number of shares of Common Stock 
     that all of the Participating Stockholders held on the date the Company 
     received the Notice of Offer.

               3.4.4 If the Retaining  Stockholders do not elect to purchase 
all of the Offered Shares available for purchase under this Section 3.4, 
Alpine shall, within 30 days following the Company's receipt of the Notice of 
Offer, notify the Company and the Selling Stockholder in writing as to the 
number of remaining Offered Shares, if any, it is electing to purchase (such 
notification is hereinafter referred to as the "Alpine Acceptance"). If 
Alpine does not provide the Alpine Acceptance to the Company and the Selling 
Stockholder within such 

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30-day period, Alpine shall be deemed to have declined to purchase any of the 
Offered Shares. The Alpine Acceptance shall be deemed to be an irrevocable 
commitment to purchase from the Selling Stockholder at the Offer Price the 
number of Offered Shares which Alpine has elected to purchase pursuant to the 
Alpine Acceptance.

               3.4.5 If the  Retaining  Stockholders  and Alpine do not elect 
to purchase all of the Offered Shares available for purchase under this 
Section 3.4, the Selling Stockholder (a) shall be under no obligation to sell 
any of the Offered Shares to any Stockholder, unless the Selling Stockholder 
so elects, and (b) may, within a period of 180 days from the date of the 
Notice of Offer, and subject to the terms and conditions of this Section 
3.4.5, sell any or all of the Offered Shares to one or more third parties 
(each a "Third Party Transferee") for cash at a price per share not less than 
the Offer Price, and on such other terms and conditions as are no more 
favorable to the proposed Third Party Transferee than those specified in the 
Notice of Offer. Upon any such sale, the Third Party Transferee of such 
Offered Shares shall execute an agreement in form and substance reasonably 
satisfactory to the Company and the Stockholders pursuant to which such Third 
Party Transferee agrees that the Offered Shares it is acquiring from the 
Selling Stockholder are subject to the provisions of this Agreement. Any 
Third Party Transferee to whom Offered Shares are transferred pursuant to and 
in compliance with this Section 3.4.5 shall, with respect to such shares upon 
consummation of such transfer, be deemed a Minority Stockholder. If the 
Selling Stockholder does not complete the sale of the Offered Shares within 
such 180-day period, the provisions of this Section 3.4 shall again apply, 
and no 

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sale of such Offered Shares by the Selling Stockholder shall be made 
otherwise than in accordance with the terms of this Agreement.

               3.4.6 The closing of purchases of Offered Shares by the 
Accepting Stockholders  and/or  Alpine  pursuant  to this  Section 3.4 shall 
take place no later than 45 days after the date of the  Notice of Offer,  at 
10:00 A.M.  local time at the  principal  offices of the Company,  or at such 
other date,  time or place as the parties to the sale may agree. At least 
five business days prior to such closing, the Company shall notify the 
Selling Stockholder in writing of the names of the purchasers and the portion 
of the Offered Shares to be purchased by each. At such closing,  the Selling 
Stockholder shall sell, transfer and deliver to each  purchaser  its or his 
full  right,  title  and  interest  in and to the Offered  Shares so  
purchased  by such  purchaser,  free and clear of all liens, security  
interests,  adverse claims or restrictions (other than those contained 
herein)  of any  kind  and  nature,  and  shall  deliver  to  each  purchaser 
 a certificate  or  certificates  representing  the  Offered  Shares  sold  
to such purchaser, in each case duly endorsed for transfer or accompanied by 
appropriate stock  transfer  powers duly  endorsed,  and any other  documents 
 necessary for transfer.  Simultaneously with the delivery of such 
certificates, each purchaser of the Offered Shares shall deliver to the 
Selling Stockholder, by wire transfer of immediately  available funds to such 
bank account as the Selling  Stockholder shall  designate,  a cash amount 
equal to the product of the Offer Price and the number of Offered  Shares 
being acquired by such  purchaser,  in full payment of the purchase price of 
the Offered Shares purchased.

          3.5  Right to Join in Sale.

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               3.5.1 If Alpine  proposes  in a single  transaction  or series 
of related  transactions  permitted  by  Section  3.3.2  and the  other  
terms  and provisions  of this  Agreement  to transfer all or a portion of 
the Common Stock held by it to one or more third  parties (a  "Transaction"), 
then Alpine  shall refrain from effecting a Transaction unless, prior to the 
consummation  thereof, the Minority  Stockholders  shall have been afforded 
the  opportunity to join in such  Transaction on a pro rata basis,  as 
hereinafter  provided.  Any purported transfer by Alpine subject to this 
Section 3.5 not made in compliance  with this Section  3.5  shall be void and 
shall  not be  consummated  upon the  books and records of the Company.

               3.5.2 Prior to the consummation of any Transaction,  Alpine 
shall cause  each  person or persons  that  propose  to  acquire  Common  
Stock in the Transaction  (the  "Proposed  Purchasers")  to offer (the  
"Purchase  Offer") in writing to  purchase  from the  Minority  Stockholders  
that number of shares of Common  Stock from each such  Minority  Stockholder  
that  constitutes  the same percentage of the  aggregate  number of shares of 
Common Stock held by each such Minority  Stockholder  as the  percentage  
determined  by dividing the number of shares of Common Stock to be purchased  
from Alpine by the  aggregate  number of shares of Common Stock held by 
Alpine,  at the same price per share, and on such other terms and  
conditions,  as the Proposed  Purchaser has offered to purchase the Common 
Stock to be sold by Alpine.  Each of the Minority  Stockholders shall have 15 
days from the  receipt  of the  Purchase  Offer in which to  accept  the 
Purchase  Offer and, to the extent any such  Minority  Stockholder  accepts 
such Purchase  Offer in  accordance  with the terms  hereof,  the number of 
shares of Common Stock to be sold by Alpine shall be reduced.

                                        18
<PAGE>


               3.5.3 The  provisions  of this Section 3.5 shall not apply to 
(w) Rule 144 Sales by Alpine  otherwise  permitted by this Agreement,  (x) a 
sale by Alpine of shares in a public  offering (it being  understood that 
nothing herein shall limit the  Minority  Stockholders'  rights under the  
Registration  Rights Agreement)  and (y) transfers by Alpine to Permitted  
Transferees  in accordance with  Section  3.2.  Alpine  shall  notify any 
third party  transferee  that the transfer  of Common  Stock  pursuant  to 
this  Section  3.5 is  subject  to this Agreement and shall ensure that no 
Transaction is consummated without compliance with this Section 3.

          3.6  Right to Require Sale.

               3.6.1 If Alpine  proposes  in a single  transaction  or series 
of related  transactions  permitted  by  Section  3.3.2  and the  other  
terms  and provisions of this  Agreement to transfer all of the shares of 
Common Stock held by it to one or more third parties,  then Alpine shall have 
the right to require each of the Minority Stockholders,  upon 15 days' 
written notice, to sell all of its or his shares of Common Stock to such 
third party(ies) at the same price per share (the "Drag-Along Price"), and on 
such other terms and conditions,  as such third  party(ies) has offered to 
purchase the Common Stock to be sold by Alpine, provided that the  Drag-Along 
Price equals or exceeds the price then payable by the  Company  upon  
exercise  of the Put  Right  (assuming  the Put  Right  were accelerated if 
it is not otherwise then exercisable); provided, however, that if the 
Drag-Along Price is not payable solely in cash or marketable securities or a 
combination   thereof,   then  in  connection  with  any  such   transaction  
or transactions,  Alpine shall  provide to the Minority  Stockholders  the 
right to require  Alpine to purchase  from the Minority  Stockholders  the  
consideration received  in such  transaction  or  transactions  other than 
cash or

                                      19

<PAGE>

marketable securities on terms and conditions that are substantially 
equivalent to the terms of the Put Right and the Accelerated Put Right (as 
defined in the Guaranty by Alpine in favor of the Minority Stockholders 
entered into on the date hereof).

               3.6.2 The  provisions  of this Section 3.6 shall not apply to 
(w) Rule 144 Sales by Alpine  otherwise  permitted by this Agreement,  (x) a 
sale by Alpine of shares in a public  offering (it being  understood that 
nothing herein shall limit the  Minority  Stockholders'  rights under the  
Registration  Rights Agreement) and (y) transfers to Permitted Transferees in 
accordance with Section 3.2. Alpine shall notify any third party  transferee 
that the transfer of Common Stock pursuant to this Section 3.6 is subject to 
this Agreement and shall ensure that no Transaction is consummated without 
compliance with this Section 3.

          Section 4. Preemptive Rights. The Company hereby grants to each of 
the Minority  Stockholders  a  preemptive  right to purchase all or any part 
of such Minority  Stockholder's  "pro rata share" (as defined in this  
Section 4) of any "New  Securities" (as defined in this Section 4) that the 
Company may, from time to time, propose to sell or issue. Such preemptive 
right shall be subject to the following provisions of this Section 4.

          4.1 "Pro Rata Share." A Minority  Stockholder's  "pro rata share," 
for purposes of this Section 4, is the ratio that (i) the number of shares of 
Common Stock then held by such Minority Stockholder bears to (ii) the total 
number of shares of Common Stock then held by all Stockholders.

                                      20
<PAGE>


          4.2 "New  Securities."  "New  Securities"  shall  mean any  shares  
of capital stock of the Company, whether now authorized or not, and any 
rights, options or warrants to purchase such shares, and any Convertible 
Securities of any type whatsoever; provided, however, that "New Securities" 
shall not include (i) securities offered to the public generally pursuant to 
an effective registration statement under the Securities Act, (ii) securities 
issued pursuant to a merger, purchase of shares, purchase of assets or other 
reorganization whereby the Company acquires not less than 20% of the voting 
power of another corporation, (iii) Common Stock issued to officers, 
directors or employees of, or independent consultants to, the Company 
pursuant to stock options granted or other employee benefit plans adopted 
after the date hereof on terms approved by the Board of Directors of the 
Company (including a majority of the members of the Board of Directors who 
are not officers or employees of the Company (or any relative thereof)), (iv) 
shares of the Company's capital stock issued pursuant to any rights or 
agreements, including, without limitation, Convertible Securities, provided 
that the preemptive rights established by this Section 4 apply with respect 
to the initial sale or grant by the Company of such rights or agreements, or 
(v) shares of the Company's capital stock issued in connection with any stock 
split, stock dividend or recapitalization by the Company.

          4.3 Procedure.  In the event that the Company proposes to undertake 
an issuance of New Securities, the Company shall give each Minority 
Stockholder written notice of its intention (the "Original Notice"), 
describing the type of New Securities and the price and material terms upon 
which the Company proposes to issue the same. Each Minority Stockholder shall 
have 15 days from the date any such Original Notice is given to agree to 
purchase all or any

                                      21
<PAGE>

part of its pro rata share of such New Securities for the price and upon the 
general terms specified in the Original Notice by giving written notice to 
the Company and stating therein the quantity of New Securities to be 
purchased. In the event that one or more, but not all, of the Minority 
Stockholders exercises in full its preemptive right within such 15-day 
period, the Company shall, upon the expiration of such 15-day period, give 
each Minority Stockholder having exercised such right (an "Exercising 
Stockholder") written notice containing the quantity of New Securities with 
respect to which any Minority Stockholder's preemptive rights were not 
exercised (the "Remaining New Securities"). Each Exercising Stockholder shall 
have 10 days from the date any such notice is given to elect to purchase all 
or any part of the Remaining New Securities for the price and upon the 
general terms specified in the Original Notice by giving written notice to 
the Company and stating therein the quantity of Remaining New Securities to 
be purchased. If the Exercising Stockholders have elected to purchase a 
number of Remaining New Securities that in the aggregate exceeds the total 
number of Remaining New Securities, the Remaining New Securities shall be 
allocated among the Exercising Stockholders on a basis consistent with the 
procedures set forth in Section 3.4.3 of this Agreement.

          4.4  Failure  to  Exercise  Preemptive  Rights.  In the event that 
any Minority or Exercising Stockholder fails to exercise in full its 
preemptive right within the aforementioned time periods, the Company shall 
have 180 days thereafter to sell the New Securities with respect to which any 
such Minority or Exercising Stockholder's preemptive rights were not 
exercised, at a price and upon general terms no more favorable to the 
purchasers thereof than specified in the Original Notice. In the event the 
Company has not sold the New Securities within such 180-day 

                               22
<PAGE>

period, the Company shall not thereafter issue or sell any New Securities 
without first offering such securities to the Minority Stockholders in the 
manner provided above.

          Section 5.     Representations and Warranties.  Each of the parties 
hereto severally as to itself or himself, and not jointly, hereby represents 
and warrants to each of the other parties to this Agreement that:

          (i) such party has the full  right,  power and  authority  to 
execute, deliver and perform this Agreement (and any other agreements or 
instruments to be executed by such party in connection herewith);

          (ii) this  Agreement  has been duly  executed  and  delivered by or 
on behalf of such party and constitutes  (and each other agreement or 
instrument to be executed by such party in connection herewith will, upon 
such execution, have been  duly  executed  and  delivered  by or on  behalf  
of such  party  and will constitute) a legal,  valid and binding  obligation  
of such party,  enforceable against such party in accordance with its terms, 
except as enforceability may be limited by bankruptcy,  insolvency or other 
similar laws affecting the rights of creditors generally or by the 
application of general equity principles;

          (iii) no consent,  approval,  authorization  or order of any Person 
is required for the  execution,  delivery or  performance of this Agreement 
(or any such other agreement or instrument) by such party;

                                      23

<PAGE>

          (iv) neither the execution, delivery nor performance of this 
Agreement (or any such other agreement or instrument) by such party will (A) 
conflict with, or result in a breach of, or constitute a default under, or 
result in a violation of, any agreement or instrument to which such party is 
a party or by which such party or its or his property is bound, or (B) result 
in the violation of any applicable law or order, judgment, writ, injunction, 
decree or award of any Governmental Authority; and

          (v) the  Common  Stock  held by such  party is being  held for its 
own account for investment and without a view to the public distribution of 
such Common Stock or any interest therein.

          Each  of the  parties  hereto  agrees  that  the  representations  
and warranties set forth in this Section 5 shall survive the execution and 
delivery of this Agreement.

          Section 6.     Termination.

          6.1 Entire Agreement.  If at any time the Minority Stockholders do 
not own any of the outstanding shares of Common Stock, this Agreement will 
terminate, without any other action by the parties or otherwise.

          6.2 Right to Designate  Directors.  If at any time the Common Stock 
is registered under the Securities Exchange Act of 1934, as amended, Section 
2 of this Agreement will terminate immediately after the first election of 
directors following the effective date of such registration, without any 
other action by the parties or otherwise. If at any time MTI (or its 

                                      24
<PAGE>

Permitted Transferees or Permitted Transferees of Permitted Transferees) or 
the Individual Refraco Stockholders collectively (or their Permitted 
Transferees or Permitted Transferees of Permitted Transferees) own less than 
2.5% of the Common Stock, Section 2 of this Agreement will terminate with 
respect to such Minority Stockholder(s), without any other action by the 
parties or otherwise.

          Section 7.  Confidentiality.  Each Stockholder agrees that, unless 
the Company otherwise consents, such Stockholder will maintain the 
confidentiality of any confidential information relating to, and provided to 
it by, Alpine, the Company or any of its subsidiaries; provided, however, 
that any Stockholder may disclose any such information (i) to such 
Stockholder's Affiliates, and to such Stockholder's and such Affiliates' 
officers, directors, employees, partners, agents, accountants, counsel and 
other professional advisors, (ii) that is or has become generally available 
to the public, (iii) as may be required or appropriate in any filing, report, 
statement or testimony submitted to any Governmental Authority, (iv) as may 
be required or appropriate in response to any summons or subpoena or in 
connection with any litigation, (v) to comply with any law, order, regulation 
or ruling applicable to such Stockholder, (vi) to the extent necessary to 
enforce the provisions of this Agreement, and (vii) to any prospective 
transferee in connection with any contemplated transfer of any of the shares 
of Common Stock (or any interest therein) by such Stockholder, provided that 
such prospective transferee agrees to be bound by this Section 7 to the same 
extent as such Stockholder.

                                    25
<PAGE>

          Section 8.     Miscellaneous.

          8.1 Specific  Performance.  Since a breach of the  provisions  of 
this Agreement could not adequately be compensated by money damages, any 
party shall be entitled, in addition to any other right or remedy available 
to it, to an injunction restraining such breach or a threatened breach and to 
specific performance of any such provision of this Agreement, and in either 
case no bond or other security shall be required in connection therewith, and 
the parties hereby consent to the issuance of such injunction and to the 
ordering of specific performance. Notwithstanding the foregoing, the parties 
agree that the Minority Stockholders shall not be entitled to, and shall not 
seek, an injunction or other temporary relief restraining the breach, alleged 
breach or threatened breach of the covenant of Alpine set forth in Section 
3.3.2 in the event that such breach, alleged breach or threatened breach 
arises out of or relates to a transaction that Alpine has notified the 
Minority Stockholders is intended to qualify as a reorganization that is 
described in clause (z) of Section 3.3.2, and the Minority Stockholders shall 
not be entitled to, and shall not seek, the ordering of specific performance 
with respect to any such matter; provided, however, that nothing herein shall 
limit, or be deemed to waive, the rights of the Minority Stockholders to seek 
monetary relief against Alpine or any other Person.

          8.2  Further  Assurances.  Each party  hereto  shall do and perform 
or cause to be done and performed all such further acts and things and shall 
execute and deliver all such other agreements, certificates, instruments and 
documents as any other party hereto reasonably may request in order to carry 
out the intent and accomplish the purposes of this Agreement.

                                      26
<PAGE>


          8.3 Governing  Law. This  Agreement and the rights and  obligations 
of the parties hereunder shall be governed by, and construed and interpreted 
in accordance with, the laws of the State of Delaware without giving effect 
to the choice of law principles thereof.

          8.4 Entire Agreement;  Amendment; Waiver. This Agreement: (a) 
contains the entire agreement among the parties hereto with respect to the 
subject matter hereof, (b) supersedes all prior written agreements and 
negotiations and oral understandings, if any, with respect thereto, and (c) 
may not be amended or supplemented except by an instrument or counterparts 
thereof in writing signed by the parties hereto. No waiver of any term or 
provision of this Agreement shall be effective unless in writing signed by 
the party to be charged. The waiver by any party of a breach of any term or 
provision of this Agreement shall not be construed as a waiver of any 
subsequent breach.

          8.5 Binding  Effect.  This Agreement  shall be binding on and inure 
to the benefit of the parties hereto and their respective Permitted 
Transferees, legal representatives, successors and Third Party Transferees; 
provided, however, that none of the rights of any Stockholder or group of 
Stockholders to designate director(s) under the provisions of Section 2 
hereof shall be transferable to a Third Party Transferee. Any transfer not in 
compliance with the provisions of this Agreement shall be null and void and 
of no effect.

          8.6 Invalidity of Provision. The invalidity or unenforceability of 
any provision of this Agreement in any jurisdiction shall not affect the 
validity or enforceability of 

                                      27
<PAGE>


the remainder of this Agreement in that jurisdiction or the validity or 
enforceability of this Agreement, including that provision, in any other 
jurisdiction.

          8.7 Notice. All notices and other  communications  provided for 
herein shall be dated and in writing and shall be deemed to have been duly 
given (x) on the date of delivery, if delivered personally or by telecopier, 
receipt confirmed, (y) on the second following business day, if delivered by 
a recognized overnight courier service, or (z) seven days after mailing, if 
sent by registered or certified mail, return receipt requested, postage 
prepaid, in each case, to the party to whom it is directed at the address set 
forth below (or at such other address as any party hereto shall hereafter 
specify by notice in writing to the other parties hereto):

          If to the Company or Alpine:

          c/o The Alpine Group, Inc.
          1790 Broadway
          New York, New York  10019-1412
          Attention:  Stewart H. Wahrsager, Esq.
          Fax:  (212) 757-3423


          with a copy to:


          Proskauer Rose LLP
          1585 Broadway
          New York, New York  10036-8299
          Attention:  Ronald R. Papa, Esq.
          Fax: (212) 969-2900


          If to MTI:


          c/o CE Minerals Inc.
          901 East 8th Avenue
          King of Prussia, Pennsylvania  19406
          Attention:  Timothy J. McCarthy
          Fax: (610) 337-1387

                                      28
<PAGE>


          with a copy to:

          Weil, Gotshal & Manges LLP
          767 Fifth Avenue
          New York, New York  10153
          Attention:  Ellen J. Odoner, Esq.
          Fax: (212) 310-8007

          If to the Individual Refraco Stockholders:

          Ralph Feuerring
          11111 Biscayne Boulevard
          Miami, Florida  33161
          Fax: (305) 893-3843

          Charles H. Gehret
          5275 Militia Hill Road
          Plymouth Meeting, Pennsylvania  19462
          Fax: (610) 649-5639

          John Gehret
          56 Crosby Brown Road
          Gladwyne, Pennsylvania  19035
          Fax: (610) 649-5639

          Stanley A. Weiss
          American Premier, Inc.
          1717 Pennsylvania Avenue, NW
          Suite 350
          Washington, DC  20006-4603
          Fax: (202) 296-8099

          with copies to:

          Duane, Morris & Heckscher LLP
          122 East 42nd Street, Suite 3300
          New York, New York 10168
          Attention:  Robert J. Hasday, Esq.
          Fax: (212) 692-1020

          and

          Bernard Petrie, Esq.

                                      29
<PAGE>

          633 Battery Street
          San Francisco, California 94111
          Fax: (415) 982-4746



          8.8  Headings;  Execution in  Counterparts.  The headings and 
captions contained herein are for convenience of reference only and shall not 
control or affect the meaning or construction of any provision hereof. This 
Agreement may be executed in any number of counterparts, each of which shall 
be deemed to be an original and all of which together shall constitute one 
and the same instrument.

                                      30
<PAGE>


          IN WITNESS WHEREOF, the parties hereto have executed this Agreement 
as of the date first above written.

                                   REFRACO INC.



                                   By: /s/ Bragi F. Schut
                                       --------------------------------------
                                       Name: Bragi F. Schut
                                       Title: Executive Vice President


                                   THE ALPINE GROUP, INC.



                                   By: /s/ Bragi F. Schut
                                       --------------------------------------
                                       Name: Bragi F. Schut
                                       Title: Executive Vice President


                                   MINERALS TRADING, INC.



                                   By: /s/ John A. Lindstrom
                                       --------------------------------------
                                       Name: John A. Lindstrom
                                       Title: Vice President

                                      /s/ Charles Gehret
                                      --------------------------------------
                                      Name: Charles Gehret

                                      /s/ John Gehret
                                      --------------------------------------
                                      Name: John Gehret

                                      /s/ Ralph Feuerring
                                      --------------------------------------
                                      Name: Ralph Feuerring

                                      /s/ Stanley Weiss
                                      --------------------------------------
                                      Name: Stanley Weiss

                                      31