Gold In Granite Amp Plutonic Rocks 911 Metallurgist. Jan 20 2017 In the goldbearing region of Northern Sonora Mexico the goldveins are chiefly in or closely associated with granitic and plutonic rocks The veins of El Grupo concession about 100 miles southeast of Tucson Arizona traverse a finegrained granite and hear both gold and silver A dioritic rock at El Plomo in the same State appears to be