MLM Martin Marietta Materials Inc

Martin Marietta Materials, Inc. (NYSE:MLM) today announced that it will provide an online Web simulcast of its third quarter 2012 earnings conference call on Tuesday, November 6, 2012. The Company will release results for the third quarter ended September 30, 2012, that morning before the market opens.

The live broadcast of Martin Marietta Materials' conference call will begin at 2:00 p.m. Eastern Time on November 6, 2012.  An online replay will be available approximately two hours following the conclusion of the live broadcast and will continue for one year. A link to these events is available at the Company's website: www.martinmarietta.com.

For those investors without online web access, the conference call may also be accessed by calling 970-315-0423, confirmation number 48690186. A five-day telephonic replay will be available by dialing 404-537-3406 and entering 48690186 when prompted for the access code.

Martin Marietta Materials is the nation's second largest producer of construction aggregates and a producer of magnesia-based chemicals and dolomitic lime. For more information about Martin Marietta Materials, refer to the Corporation's website at www.martinmarietta.com.  

CONTACT: Anne Lloyd
         Executive Vice President, Chief Financial
         Officer and Treasurer
         (919) 783-4660
         www.martinmarietta.com