FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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(Print or Type Responses)

1. Name and Address of Reporting Person *   Riordan Thomas 2. Date of Event Requiring Statement (Month/Day/Year) 08/12/2005 3. Issuer Name and Ticker or Trading Symbol Rockwood Holdings, Inc. [ROC] (Last) (First) (Middle) 100 OVERLOOK CENTER 4. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) Sr. VP, Law & Administration 5. If Amendment, Date Original Filed(Month/Day/Year) (Street) PRINCETON, NJ 08540 6. Individual or Joint/Group Filing(Check Applicable Line) _X_ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Beneficially Owned

1.Title of Security (Instr. 4) 2. Amount of Securities Beneficially Owned (Instr. 4) 3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 4. Nature of Indirect Beneficial Ownership (Instr. 5) Common Stock, par value $0.01 per share 51,338 D Â

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.			SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Employee Stock Options (right to buy)	  (1)	02/02/2011	Common Stock	68,451	$ 14.61	D	Â
Employee Stock Options (right to buy)	  (2)	10/15/2014	Common Stock	34,225	$ 14.61	D	Â
Employee Stock Options (right to buy)	  (3)	02/02/2011	Common Stock	68,451	$ 14.61	D	Â
Employee Stock Options (right to buy)	  (4)	10/15/2014	Common Stock	68,451	$ 14.61	D	Â

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Riordan Thomas 100 OVERLOOK CENTER PRINCETON, NJ 08540	Â	Â	  Sr. VP, Law & Administration	Â

Signatures

/s/ Thomas J. Riordan		08/12/2005
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 5(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	These options were granted on February 2, 2001 and vest 10% on each of the first and second anniversary of the vesting date, 25% on each of the third and fourth anniversary of the vesting date and 30% on the fifth anniversary of the vesting date.
(2)	These options were granted on October 15, 2004 and vest in five equal annual installments beginning October 15, 2005.
(3)	These options vest on February 2, 2009, but may vest earlier upon the satisfaction of certain performance targets.
(4)	These options vest on October 15, 2012, but may vest earlier upon the satisfaction of certain performance targets.

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