NL INDUSTRIES INC — Director's Dealing 2004

May 24, 2004

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: KRONOS WORLDWIDE INC (KRO)
CIK: 0001257640
Period of Report: 2004-05-20

Reporting Person: SIMMONS HAROLD C (Director, Chairman of the Board and CEO, 10% Owner)
Reporting Person: CONTRAN CORP (10% Owner)
Reporting Person: NATIONAL CITY LINES INC (10% Owner)
Reporting Person: NL INDUSTRIES INC (10% Owner)
Reporting Person: TREMONT LLC (10% Owner)
Reporting Person: DIXIE HOLDING CO (10% Owner)
Reporting Person: DIXIE RICE AGRICULTURE CORP INC (10% Owner)
Reporting Person: NOA INC (10% Owner)
Reporting Person: SOUTHWEST LOUISIANA LAND CO INC (10% Owner)
Reporting Person: VALHI INC /DE/ (10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2004-05-20	Common Stock, $0.01 par value	A	500	—	Acquired	3670	Direct
2004-05-21	Common Stock, $0.01 par value	J	400	$30.30	Acquired	16134748	Indirect
2004-05-21	Common Stock, $0.01 par value	J	400	$30.56	Acquired	16135148	Indirect
2004-05-21	Common Stock, $0.01 par value	J	1600	$30.75	Acquired	16136748	Indirect
2004-05-21	Common Stock, $0.01 par value	J	1000	$31.00	Acquired	16137748	Indirect

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock, $0.01 par value	24702400	Indirect
Common Stock, $0.01 par value	5180738	Indirect
Common Stock, $0.01 par value	35233	Indirect

Footnotes

F1: Shares issued for no cash consideration to directors under the Kronos Worldwide, Inc. 2003 Long-Term Incentive
Plan.

F2: Open market purchase by Valhi, Inc. See the Additional Information filed as an exhibit to this statement for a description
of the relationships among the persons joining in this filing.

F3: Directly held by Valhi, Inc. See the Additional Information filed as an exhibit to this statement for a description of the
relationships among the persons joining in this filing.

F4: Directly held by NL Industries, Inc. See the Additional Information filed as an exhibit to this statement for a description
of the relationships among the persons joining in this filing.

F5: Directly held by Tremont LLC. See the Additional Information filed as an exhibit to this statement for a description of the
relationships among the persons joining in this filing.

F6: The reporting person disclaims beneficial ownership of these shares.