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Exhibit 10.39

EXECUTION COPY

STOCK OPTION AGREEMENT
(Time and Performance)

        This Stock Option Agreement (the "Agreement"), dated as of September 24,
2004 (the "Grant Date"), is made by and between Rockwood Holdings, Inc., a
Delaware corporation (hereinafter referred to as the "Company"), and Seifollah
Ghasemi, an employee of the Company or a Subsidiary (as defined in the Plan) or
an Affiliate (as defined below) of the Company, hereinafter referred to as
"Optionee".

        WHEREAS, the Committee (as defined below), appointed to administer the
Plan, has determined that it would be to the advantage and best interest of the
Company and its shareholders to grant the Optionee an option to purchase shares
of its common stock, par value $0.01 per share (the "Common Stock") as an
incentive for increased efforts during the Optionee's term of employment with
the Company or its Subsidiaries or Affiliates;

        NOW, THEREFORE, in consideration of the mutual covenants herein
contained and other good and valuable consideration, receipt of which is hereby
acknowledged, the parties hereto do hereby agree as follows:

ARTICLE I

DEFINITIONS

        Whenever the following terms are used in this Agreement, they shall have
the meaning specified in the Plan or below unless the context clearly indicates
to the contrary.

Section 1.1.    Affiliate    

        "Affiliate" shall mean, with respect to the Company, any entity directly
or indirectly controlling, controlled by, or under common control with, the
Company or any other entity designated by the Board of Directors of the Company
in which the Company or an Affiliate has an interest.

Section 1.2.    Cause    

        "Cause" shall mean (i) the Optionee's willful and continued refusal to
perform duties, which are within the control of the Optionee and consistent with
the Optionee's title and position, that is not cured within 15 days following
receipt by the Optionee of written notice from the Company of such failure,
(ii) the Optionee's conviction of or plea of guilty or no contest to a
(x) felony, (y) a misdemeanor involving the Company or (z) misdemeanor not
involving the Company, which results in material and demonstrable harm to the
business or reputation of the Company (in each case of (x), (y) or (z), other
than as a result of vicarious liability under any environmental criminal
statute), (iii) the Optionee's willful malfeasance or misconduct (x) relating to
the Company which is demonstrably injurious to the Company or its subsidiaries,
other than in a manner that is insignificant or inconsequential or (y) not
involving the Company, but which results in material, adverse and demonstrable
harm to the Company or its subsidiaries or (iv) a breach by the Optionee of the
material terms of Section 25 of the Management Stockholder's Agreement,
following notice of such breach (which notice may be oral or written) that (if,
in the good faith discretion of the Board, is able to be cured by the Optionee)
is not cured within 15 days following receipt by the Optionee of written notice
from the Company that it reasonably believes the Optionee is in breach of any
such covenants; provided, however, that Cause shall cease to exist as an event
on the 60th day following actual and substantiated knowledge of the Cause event
by a non-employee member of the Board affiliated with KKR. For purposes of this
subsection, no act, or failure to act, on the Optionee's part shall be
considered "willful" unless done or omitted to be done, by him not in good faith
and without reasonable belief that his action or omission was in the best
interests of the Company.

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Section 1.3.    Change of Control    

        "Change of Control" shall mean (i) sales of all or substantially all of
the assets of the Company to a Person who is not KKR or an affiliate of KKR
(collectively, the "KKR Partnerships"), (ii) a sale by KKR or any of its
respective affiliates resulting in more than 50% of the voting stock of the
Company being held by a Person or group that does not include KKR or any of its
respective affiliates or (iii) a merger, consolidation, recapitalization or
reorganization of the Company with or into another Person which is not an
affiliate of KKR; if and only if as a result of any of the foregoing events in
(i)-(iii) the KKR Partnerships lose the ability, without the approval of a
Person who is not an affiliate of KKR, to elect a majority of the Board of
Directors of the Company (or the resulting entity). Notwithstanding the
foregoing, if any of the transactions described in (i)-(iii) of the preceding
sentence shall occur and the other Person involved in such transaction (or its
ultimate parent entity) is an operating company controlled by KKR or an
affiliate of KKR prior to such transaction (an "Alternate KKR Entity"), then the
determination of whether a change of control has occurred shall be made by
determining whether an event set forth in clauses (i), (ii) or (iii) above has
occurred (including the ability to elect a majority of the Board) if the
Alternate KKR Entity is treated as being unaffiliated with KKR and by treating
the voting power of the Alternate KKR Entity in the Company (or the resulting
entity) as if it were held by a Person unaffiliated with KKR.

Section 1.4.    Code    

        "Code" shall mean the Internal Revenue Code of 1986, as amended.

Section 1.5.    Committee    

        "Committee" shall mean the Compensation Committee of the Company.

Section 1.6.    Disability    

        "Disability" shall mean a determination, made at the request of the
Optionee or upon the reasonable request of the Company set forth in a notice to
the Optionee, by a physician selected by the Company and the Optionee, that the
Optionee is unable to perform his duties as an employee of the Company or its
subsidiaries and in all reasonable medical likelihood such inability will
continue for a period in excess of 180 consecutive days (such inability is
hereinafter referred to as "Disability" or being "Disabled").

Section 1.7.    Financial Statement Approval Date    

        "Financial Statement Approval Date" shall mean the date on which the
audited financial statements of the Company for any given Fiscal Year have been
finally approved by the auditing firm engaged by the Company to review such
statements (which approval shall in no event occur later than March 31 of the
calendar year immediately following the applicable Fiscal Year).

Section 1.8.    Fiscal Year    

        "Fiscal Year" shall mean each fiscal year of the Company.

Section 1.9.    Good Reason    

        "Good Reason" shall mean, without the Optionee's consent, (A) a
reduction in the Optionee's base salary or annual bonus opportunity, (B) a
substantial reduction in the Optionee's duties, authorities, and
responsibilities or removal from the Optionee of the title of Chief Executive
Officer of the Company, (C) the Optionee's removal from, or failure to be
re-elected to the Board, (D) the elimination or reduction of the Optionee's
eligibility to participate in the Company's benefit programs that is
inconsistent with the eligibility of similarly situated employees of the Company
to participate therein, provided, however, that any adverse change to the terms
of the Supplemental Pension Benefit shall be deemed an event of Good Reason,
(E) a transfer of the Optionee's primary workplace by more

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than 35 miles from the Company's offices in Princeton, New Jersey, (F) any
failure by the Company to pay when due any payment owed to the Optionee within
15 days after the date such payment becomes due or (G) failure of any successor
to the Company (whether direct or indirect and whether by merger, acquisition,
consolidation or otherwise) to assume in a writing delivered to the Optionee,
upon the assignee becoming such, the obligations of the Company hereunder;
provided, that either of the events described in clauses (A) and (B) of this
definition shall constitute Good Reason only if the Company fails to cure such
event within 30 days after receipt from the Optionee of written notice of the
event which constitutes Good Reason; and provided, further, that "Good Reason"
shall cease to exist for an event on the 60th day following the later of its
occurrence or the Optionee's knowledge thereof, unless the Optionee has given
the Company written notice thereof prior to such date.

Section 1.10.    Group    

        "Group" shall mean two or more Persons acting together as a partnership,
limited partnership, syndicate or other group for the purpose of acquiring,
holding or disposing of securities of the Company.

Section 1.11.    Initial Vesting Date    

        "Initial Vesting Date" shall mean the Grant Date.

Section 1.12.    Interim Termination Event    

        "Interim Termination Event" shall mean any event that terminates the
Optionee's employment described in Section 3.2(b) or (c) below, which occurs
after December 31 of any given calendar year but prior to the Financial
Statement Approval Date occurring in the immediately following calendar year.

Section 1.13.    Management Stockholder's Agreement    

        "Management Stockholder's Agreement" shall mean that certain Amended and
Restated Management Stockholder's Agreement dated as of September 24, 2004
between the Optionee and the Company, as amended from time to time.

Section 1.14.    Options    

        "Options" shall mean the Time Option (which shall, in part and to the
extent permitted by applicable law and as set forth on the signature page
hereto, be an "incentive stock option", within the meaning of Section 422 of the
Code) and Performance Option (which shall in its entirety be an option that is
not an incentive stock option) to purchase Common Stock granted under this
Agreement. To the extent that, for any reason, an Option intended to be an
incentive stock option does not qualify as an incentive stock option, it shall
be deemed an Option that is not an incentive stock option.

Section 1.15.    Performance Option    

        "Performance Option" shall mean an Option with respect to which the
commencement of exercisability is governed by Section 3.1(b) hereof.

Section 1.16.    Performance Target    

        "Performance Target" shall have the meaning as set forth in Appendix A
attached hereto.

Section 1.17.    Person    

        "Person" shall mean "person", as such term is used for purposes of
Section 13(d) or 14(d) of the Securities Exchange Act of 1934, as amended (or
any successor section thereto).

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Section 1.18.    Plan    

        "Plan" shall mean the Amended and Restated 2003 Stock Purchase and
Option Plan for Rockwood Holdings, Inc. and Subsidiaries.

Section 1.19.    Pronouns    

        The masculine pronoun shall include the feminine and neuter, and the
singular the plural, where the context so indicates.

Section 1.20.    Retirement    

        "Retirement" shall mean retirement at age 65 or over (or such other age
as may be approved by the Board of Directors of the Company) after having been
employed by the Company or a Subsidiary for at least three years after
November 1, 2001.

Section 1.21.    Secretary    

        "Secretary" shall mean the Secretary of the Company.

Section 1.22.    Time Option    

        "Time Option" shall mean an Option with respect to which the
commencement of exercisability is governed by Section 3.1(a) hereof.

Section 1.23.    Vesting Date    

        "Vesting Date" shall mean each anniversary of the Initial Vesting Date
on which the Time Option becomes exercisable pursuant to
Section 3.1(a)(i) hereof.

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ARTICLE II

GRANT OF OPTIONS

Section 2.1.    Grant of Options

        For good and valuable consideration, on and as of the date hereof the
Company irrevocably grants to the Optionee a Time Option and a Performance
Option to purchase any part or all of an aggregate of the number of shares set
forth with respect to each such Option on the signature page hereof of its
Common Stock upon the terms and conditions set forth in this Agreement.

Section 2.2.    Exercise Price

        Subject to Section 2.4, the exercise price of the shares of Common Stock
covered by the Options shall be $500.00 per share without commission or other
charge (which is the fair market value per share of the Common Stock on the
Grant Date).

Section 2.3.    No Guarantee of Employment

        Nothing in this Agreement or in the Plan shall confer upon the Optionee
any right to continue in the employ of the Company or any Subsidiary or
Affiliate or shall interfere with or restrict in any way the rights of the
Company and its Subsidiaries or Affiliates, which are hereby expressly reserved,
to terminate the employment of the Optionee at any time for any reason
whatsoever, with or without Cause.

Section 2.4.    Adjustments in Options Pursuant to Merger, Consolidation, etc.

        Subject to Sections 8 and 9 of the Plan, in the event that the
outstanding shares of the stock subject to an Option, are, from time to time,
changed into or exchanged for a different number or kind of shares of the
Company or other securities of the Company by reason of a merger, consolidation,
recapitalization, reclassification, stock split, stock dividend, combination of
shares, or other corporate event, the Committee shall make, as appropriate and
equitable, an adjustment in the number and kind of shares and/or the amount of
consideration as to which or for which, as the case may be, such Option, or
portions thereof then unexercised, shall be exercisable and/or, other than in an
event that is a Change of Control, shall pay to the Optionee a dividend in
respect of the shares of Common Stock subject to the Option, in any event in
order to allow the Optionee to participate in such corporate event in an
equitable manner. Any such adjustment made by the Committee shall be final and
binding upon the Optionee, the Company and all other interested persons.

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ARTICLE III

PERIOD OF EXERCISABILITY

        Section 3.1.    Commencement of Exercisability    

        (a)   Time Option.

        (i)    So long as the Optionee continues to be employed by the Company
or its Subsidiaries, the Time Option shall become exercisable pursuant to the
following schedule:

Date Time Option
Becomes Exercisable

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  Percentage of Time Option Shares
Granted As to Which Time
Option Is Exercisable

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  After the first anniversary of the Initial Vesting Date   20 % After the
second anniversary of the Initial Vesting Date   40 % After the third
anniversary of the Initial Vesting Date   60 % After the fourth anniversary of
the Initial Vesting Date   80 % After the fifth anniversary of the Initial
Vesting Date   100 %

        (ii)   That portion of the Option intended to be an "incentive stock
option" within the meaning of Section 422 of the Code ("ISO") and that portion
of the Option that is not intended to be an ISO ("NQSO") shall each become
exercisable ratably in accordance with the above schedule. For example,
following the first anniversary of the Initial Vesting Date, 20% of the ISOs and
20% of the NQSOs shall be exercisable, while 40% of the ISOs and 40% of the
NQSOs shall be exercisable following the second anniversary of the Initial
Vesting Date, and so on.

        (iii)  Notwithstanding the foregoing, the Time Option shall become
immediately exercisable as to 100% of the shares of Common Stock subject to such
Option immediately prior to a Change of Control (but only to the extent such
Option has not otherwise terminated or become exercisable).

        (b)   Performance Option.

        (i)    The Option shall become exercisable with respect to 20% of the
shares of Common Stock subject to such Option in respect of each Fiscal Year
(beginning with the 2004 Fiscal Year) upon the achievement by the Company of the
Performance Target established in respect of each such Fiscal Year and set forth
on Appendix A attached hereto; provided, however, that such Option shall only
become exercisable as to 20% of the shares of Common Stock subject to such
Option (each such 20% of the shares, a "Tranche") on December 31 of each such
Fiscal Year upon the occurrence of the Financial Statement Approval Date
applicable to such Fiscal Year so long as either (i) the Optionee remains
employed with the Company on the applicable Financial Statement Approval Date or
(ii) an Interim Termination Event occurs between such December 31 and the
applicable Financial Statement Approval Date. If the Company does not achieve
its Performance Target for any given Fiscal Year (a "Missed Year"), the Option
shall not become exercisable in respect of such Fiscal Year, as set forth in the
immediately preceding sentence; provided, however, that if the Company achieves
the Performance Target as established for any Fiscal Year subsequent to a Missed
Year, then any prior percentage of the Option (the exercisability of which had
not previously occurred) in respect of prior Missed Years shall become
exercisable (but only to the extent such Option has not otherwise terminated or
become exercisable). Notwithstanding the foregoing, the Option shall become
exercisable as to 100% of the shares of Common Stock subject to such Option (to
the extent such Option has not otherwise terminated or become exercisable) on
the eighth anniversary of the Grant Date.

        (ii)   Notwithstanding the foregoing, upon the occurrence of a Change of
Control prior to December 31, 2008, the Option (to the extent such Option has
not otherwise terminated) shall be exercisable with respect to the number of
shares of Common Stock equal to the total number of shares of Common Stock
subject to the Option multiplied by a fraction, (i) the numerator of which

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is the number of shares of Common Stock that have previously become exercisable
in respect of prior Fiscal Years, plus, with respect to the Tranche that could
have become vested in respect the Fiscal Year in which the Change of Control
occurs, if the Board determines, in its good faith discretion that, as of the
date of the Change of Control, the Company would, but for the Change of Control,
have achieved the Performance Target for such year, a pro rata portion of such
Tranche (based on the number of days that have elapsed in such Fiscal Year
through the date of the Change of Control, relative to 365 days) (the "Pro-Rata
Fiscal Year") and (ii) the denominator of which is the maximum number of shares
that could have become vested in such completed Fiscal Years (whether or not
they actually vested), plus a pro-rata portion of the maximum number of shares
that could have become vested for the Fiscal Year in which the Change of Control
occurred. (See Exhibit I for an example of the application of this
Section 3.1(b)(ii).) Notwithstanding the foregoing provisions of this
Section 3.1(b), if the Board determines, in its good faith discretion, that, as
of the date of the Change of Control, the Company achieved the applicable
Performance Target set forth in Appendix A hereto, the Option shall become
exercisable in full. The Board shall make such determination based on an
interpolation of the applicable Fiscal Year goals set forth in Appendix A.

        (c)   Notwithstanding the foregoing, no Option which does not otherwise
become exercisable in accordance with Section 3.1(b)(i) above shall become
exercisable as to any additional shares of Common Stock following the
termination of employment of the Optionee for any reason, and any Option which
is non-exercisable as of the Optionee's termination of employment (other than
any Option which becomes exercisable in accordance with Section 3.1(b)(i) shall
be immediately cancelled.

Section 3.2.    Expiration of Options

        Except as otherwise provided in Section 5 or 6 of the Management
Stockholder's Agreement, the Optionee may not exercise the Options to any extent
after the first to occur of the following events:

        (a)   The tenth anniversary of the Grant Date;

        (b)   The tenth anniversary of the Grant Date, if the Optionee's
employment is terminated by reason of death or Disability;

        (c)   The first anniversary of the date of the Optionee's termination of
employment by reason of Retirement, by the Company without Cause or by the
Optionee for Good Reason;

        (d)   The date of an Optionee's termination of employment by the Company
for any reason other than as set forth in Section 3.2(b) or (c) above (without
regard to Section 5 or 6 of the Management Stockholder's Agreement);

        (e)   The date the Option is terminated pursuant to Section 5 or 6 of
the Management Stockholder's Agreement; or

        (f)    If the Committee so determines pursuant to Section 9 of the Plan,
the effective date of either the merger or consolidation of the Company into
another Person, or the exchange or acquisition by another Person of all or
substantially all of the Company's assets or 80% or more of its then outstanding
voting stock, or the recapitalization, reclassification, liquidation or
dissolution of the Company. At least ten days prior to the effective date of
such merger, consolidation, exchange, acquisition, recapitalization,
reclassification, liquidation or dissolution, the Committee shall give the
Optionee notice of such event if the Option has then neither been fully
exercised nor become unexercisable under this Section 3.2.

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ARTICLE IV

EXERCISE OF OPTIONS

Section 4.1.    Person Eligible to Exercise

        Except as otherwise provided in the Management Stockholder's Agreement,
during the lifetime of the Optionee, only he may exercise an Option or any
portion thereof. After the death of the Optionee, any exercisable portion of an
Option may, prior to the time when an Option becomes unexercisable under
Section 3.2, be exercised by his personal representative or by any person
empowered to do so under the Optionee's will or under the then applicable laws
of descent and distribution.

Section 4.2.    Partial Exercise

        Any exercisable portion of an Option or the entire Option, if then
wholly exercisable, may be exercised in whole or in part at any time prior to
the time when the Option or portion thereof becomes unexercisable under
Section 3.2; provided, however, that any partial exercise shall be for whole
shares of Common Stock only.

Section 4.3.    Manner of Exercise

        An Option, or any exercisable portion thereof, may be exercised solely
by delivering to the Secretary or his office all of the following prior to the
time when the Option or such portion becomes unexercisable under Section 3.2:

        (a)   Notice in writing signed by the Optionee or the other person then
entitled to exercise the Option or portion thereof, stating that the Option or
portion thereof is thereby exercised and indicating the extent to which the
portion of the Option being exercised constitutes Incentive Stock Options, such
notice complying with all applicable rules established by the Committee;

        (b)   Full payment (in cash, by check or by a combination thereof) for
the shares with respect to which such Option or portion thereof is exercised;

        (c)   A bona fide written representation and agreement, in a form
satisfactory to the Committee, signed by the Optionee or other person then
entitled to exercise such Option or portion thereof, stating that the shares of
stock are being acquired for his own account, for investment and without any
present intention of distributing or reselling said shares except as may be
permitted under the Securities Act of 1933, as amended (the "Act"), and then
applicable rules and regulations thereunder, and that the Optionee or other
person then entitled to exercise such Option or portion thereof will indemnify
the Company against and hold it free and harmless from any loss, damage, expense
or liability resulting to the Company if any sale or distribution of the shares
by such person is contrary to the representation and agreement referred to
above; provided, however, that the Committee may, in its reasonable discretion,
take whatever additional actions it deems reasonably necessary to ensure the
observance and performance of such representation and agreement and to effect
compliance with the Act and any other federal or state securities laws or
regulations;

        (d)   Full payment to the Company of all amounts which, under federal,
state or local law, it is required to withhold upon exercise of the Option; and

        (e)   In the event the Option or portion thereof shall be exercised
pursuant to Section 4.1 by any person or persons other than the Optionee,
appropriate proof of the right of such person or persons to exercise the Option.

Without limiting the generality of the foregoing, the Committee may require an
opinion of counsel acceptable to it to the effect that any subsequent transfer
of shares acquired on exercise of an Option does not violate the Act, and may
issue stop-transfer orders covering such shares. Share certificates

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evidencing stock issued on exercise of this Option shall bear an appropriate
legend referring to the provisions of subsection (c) above and the agreements
herein. The written representation and agreement referred to in subsection
(c) above shall, however, not be required if the shares to be issued pursuant to
such exercise have been registered under the Act, and such registration is then
effective in respect of such shares. In addition to the foregoing, after a
Public Offering (as defined in the Management Stockholder's Agreement), the
Optionee may, in the Committee's good faith discretion, make payment of the
exercise price (as required in Section 4.3(b) above) in shares of Common Stock
that the Optionee has held for at least six months or otherwise pursuant to an
irrevocable broker loan program established in accordance with applicable law.

Section 4.4.    Conditions to Issuance of Stock Certificates

        The shares of stock deliverable upon the exercise of an Option, or any
portion thereof, may be either previously authorized but unissued shares or
issued shares, which have then been reacquired by the Company. Such shares shall
be fully paid and nonassessable. The Company shall not be required to issue or
deliver any certificate or certificates for shares of stock purchased upon the
exercise of an Option or portion thereof prior to fulfillment of all of the
following conditions:

        (a)   The obtaining of approval or other clearance from any state or
federal governmental agency which the Committee shall, in its reasonable and
good faith discretion, determine to be necessary or advisable; and

        (b)   The lapse of such reasonable period of time following the exercise
of the Option as the Committee may from time to time establish for reasons of
administrative convenience.

Section 4.5.    Rights as Stockholder

        The holder of an Option shall not be, nor have any of the rights or
privileges of, a stockholder of the Company in respect of any shares purchasable
upon the exercise of the Option or any portion thereof unless and until
certificates representing such shares shall have been issued by the Company to
such holder.

ARTICLE V

MISCELLANEOUS

Section 5.1.    Administration

        The Committee shall have the power to interpret the Plan and this
Agreement and to adopt such rules for the administration, interpretation and
application of the Plan as are consistent therewith and to interpret or revoke
any such rules. All actions taken and all interpretations and determinations
made by the Committee shall be final and binding upon the Optionee, the Company
and all other interested persons. No member of the Committee shall be personally
liable for any action, determination or interpretation made in good faith with
respect to the Plan or the Options. In its absolute discretion, the Board of
Directors may at any time and from time to time exercise any and all rights and
duties of the Committee under the Plan and this Agreement.

Section 5.2.    Options Not Transferable

        Except as provided in the Management Stockholder's Agreement, neither
the Options nor any interest or right therein or part thereof shall be liable
for the debts, contracts or engagements of the Optionee or his successors in
interest or shall be subject to disposition by transfer, alienation,
anticipation, pledge, encumbrance, assignment or any other means whether such
disposition be voluntary or involuntary or by operation of law by judgment,
levy, attachment, garnishment or any other legal or equitable proceedings
(including bankruptcy), and any attempted disposition thereof shall

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be null and void and of no effect; provided, however, that this Section 5.2
shall not prevent transfers by will or by the applicable laws of descent and
distribution.

Section 5.3.    Shares to Be Reserved

        The Company shall at all times during the term of the Options reserve
and keep available such number of shares of stock as will be sufficient to
satisfy the requirements of this Agreement.

Section 5.4.    Notices

        Any notice to be given under the terms of this Agreement to the Company
shall be addressed to the Company in care of its Secretary, and any notice to be
given to the Optionee shall be addressed to him at the address given beneath his
signature hereto. By a notice given pursuant to this Section 5.4, either party
may hereafter designate a different address for notices to be given to him. Any
notice, which is required to be given to the Optionee, shall, if the Optionee is
then deceased, be given to the Optionee's personal representative if such
representative has previously informed the Company of his status and address by
written notice under this Section 5.4. Any notice shall have been deemed duly
given when enclosed in a properly sealed envelope or wrapper addressed as
aforesaid, deposited (with postage prepaid) in a post office or branch post
office regularly maintained by the United States Postal Service.

Section 5.5.    Titles

        Titles are provided herein for convenience only and are not to serve as
a basis for interpretation or construction of this Agreement.

Section 5.6.    Applicability of Plan and Management Stockholder's Agreement

        The Options and the shares of Common Stock issued to the Optionee upon
exercise of the Options shall be subject to all of the terms and provisions of
the Plan and the Management Stockholder's Agreement, to the extent applicable to
the Options and such shares. In the event of any conflict between this Agreement
and the Plan, the terms of the Plan shall control. In the event of any conflict
between this Agreement or the Plan and the Management Stockholder's Agreement,
the terms of the Management Stockholder's Agreement shall control.

Section 5.7.    Amendment

        This Agreement may be amended only by a writing executed by the parties
hereto, which specifically states that it is amending this Agreement.

Section 5.8.    Governing Law

        The laws of the State of Delaware shall govern the interpretation,
validity and performance of the terms of this Agreement regardless of the law
that might be applied under principles of conflicts of laws.

Section 5.9.    Arbitration

        In the event of any controversy among the parties hereto arising out of,
or relating to, this Agreement which cannot be settled amicably by the parties,
such controversy shall be finally, exclusively and conclusively settled by
mandatory arbitration conducted expeditiously in accordance with the American
Arbitration Association rules, by a single independent arbitrator. If the
parties are unable to agree on the selection of an arbitrator, then any party
may petition the American Arbitration Association for the appointment of the
arbitrator, which appointment shall be made within ten days of the petition
therefore. Either the Company or the Optionee may institute such arbitration
proceeding by giving written notice to the other party. The arbitrator in New
York or New Jersey shall hold a hearing within 30 days of his or her
appointment. In preparation for their presentation at such hearing, each party
may depose a maximum of four people. Each such deposition shall last no more
than six

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hours. Each side may file with the arbitrator one brief, not in excess of 30
pages, excluding exhibits. Each side shall have no more than eight hours to
present its position to the arbitrator. The hearing shall be no more than three
days in length. The decision of the arbitrator shall be final and binding upon
all parties hereto and shall be rendered pursuant to a written decision, which
contains a detailed recital of the arbitrator's reasoning. Judgment upon the
award rendered may be entered in any court having jurisdiction thereof.

        IN WITNESS WHEREOF, this Agreement has been executed and delivered by
the parties hereto.

    ROCKWOOD HOLDINGS. INC.
 
 
By:
/s/  THOMAS J. RIORDAN      

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Thomas J. Riordan
Its:    Senior Vice President Law and Administration
 
 
OPTIONEE:
 
 
By:
/s/  SEIFOLLAH GHASEMI      

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SEIFOLLAH GHASEMI
 
 

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    Address
 
 
Optionee's Taxpayer Identification Number:
 
 

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Aggregate number of shares of Common Stock for which the Time Option granted
hereunder is exercisable (40% of total number of shares):       6,000, of which
      200     shall be incentive stock options and       5,800 shall be
nonqualified stock options.      
Aggregate number of shares of Common Stock for which the Performance Option
granted hereunder is exercisable (60% of total number of shares):
 
 
  9,000, all of which shall be non-qualified stock options.      

11

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Appendix A
Performance Targets

        The Performance Targets are based on the Company's achievement of the
following implied equity values calculated as 8.0x the applicable fiscal year's
Consolidated EBITDA (as defined below), minus the year-end Net Debt (as defined
below, and, with Consolidated EBITDA, "Equity Values"):

Fiscal Year

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  Equity Values

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2004:   $868.7 million 2005:   $1,290.1 million 2006:   $1,822.2 million 2007:  
$2,401.6 million 2008:   $2,785.0 million

For purposes hereof,

        (a)   "Consolidated EBITDA" is as defined in the Credit Agreement dated
as of July 30, 2004 among Rockwood Specialties Group, Inc., Rockwood Specialties
Limited, Rockwood Specialties International, Inc., the lenders party thereto,
Credit Suisse First Boston, acting through its Cayman Islands Branch, as
administrative agent and collateral agent, and UBS Securities LLC and Goldman
Sachs Credit Partners L.P., as co-syndication agents thereunder, filed as
Exhibit 10.1 to Rockwood Specialties Group, Inc.'s Current Report on Form 8-K
filed with the Securities and Exchange Commission on August 4, 2004 ("Credit
Agreement").

        (b)   "Net Debt" is "Consolidated Total Debt" as defined in the Credit
Agreement, plus (i) all net indebtedness of Rockwood Specialties
International, Inc. and Rockwood Specialties Consolidated, Inc. for borrowed
money outstanding on such date and (ii) all Capitalized Lease Obligations of
Rockwood Specialties International, Inc. and Rockwood Specialties
Consolidated, Inc. outstanding on such date.

        The Board shall, in good faith, fairly and appropriately adjust the
effect(s) of any significant acquisitions, divestitures, foreign exchange
movements, changes in capital structure, and other non-recurring or
extraordinary events that may affect the Equity Values, based on an objective
determination that such an adjustment is reasonably necessary. The Board's
determination of such adjustment shall be based on the Company's accounting as
set forth in its books and records and on the financial plan of the Company
pursuant to which the Equity Values were originally established.

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Exhibit I

Example

Assumptions:

(1)100 shares of stock subject to the option (irrespective of whether such
options have previously been exercised).

(2)FY 2004 Performance Target achieved, the option vested, and was exercised, as
to 20 shares.

(3)FY 2005 Performance Target not achieved.

(4)FY 2006: Change of Control occurs mid-year; Board of Directors determines the
Company is on target to achieve FY 2006 Performance Target.

Result:

        Based on the special Change of Control vesting schedule, the proportion
of the total shares subject to the option (irrespective of any prior exercise)
is determined as follows:

Total Shares subject to option   Change of Control Vesting Fraction     100  
20 + 10
50   = 60 shares

        Since 20 shares have already vested, an additional 40 shares of the
original 100 shares would become vested upon the Change of Control.

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QuickLinks

Exhibit 10.39

EXECUTION COPY

STOCK OPTION AGREEMENT (Time and Performance)
ARTICLE I DEFINITIONS
ARTICLE II GRANT OF OPTIONS
ARTICLE III PERIOD OF EXERCISABILITY
ARTICLE IV EXERCISE OF OPTIONS
ARTICLE V MISCELLANEOUS
Appendix A Performance Targets
Exhibit I Example