Just discovered that Alexander already left GM in May 2010.
"Before that, he was the Corporate Controller for Golden Minerals Company (successor to Apex Silver Mines Limited), a U.S. and Canadian publicly traded international mining company with operations and exploration activities in South America and Mexico from July 2007 to May 2010".
http://www.hotstocked.com/8-k/pershing-gold-corp-PGLC-2108952.html