RALEIGH, N.C., April 23, 2013 (GLOBE NEWSWIRE) -- Martin Marietta Materials, Inc. (NYSE:MLM) today announced that it will provide an online Web simulcast of its first quarter 2013 earnings conference call on Tuesday, April 30, 2013. The Company will release results for the first quarter ended March 31, 2013, 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 April 30, 2013.  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 43776746. A five-day telephonic replay will be available by dialing 404-537-3406 and entering 43776746 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. MLM-E
CONTACT: Anne Lloyd         Executive Vice President, Chief Financial Officer         and Treasurer         (919) 783-4660         www.martinmarietta.com