 RALEIGH, N.C., July 15, 2021 GLOBE NEWSWIRE -- Martin Marietta Materials, Inc. NYSE:MLM Martin Marietta or the Company will host its second-quarter 2021 earnings conference call on Thursday, July 29, 2021 at 11:00 a.m. Eastern Time. The Company will release results for the quarter ended June 30, 2021, that morning before the market opens. 