Fineness of Placer GoldPlacer gold will not be .999 fine. The placer gold that was mined in the 1849 California Gold Rush was as "impure" as .700 fine, alloyed with silver copper etc at the time of deposition in the original "vein"... erosion has freed it from the rock and water has transported and concentrated the gold in the alluvium. So depending on the fineness of the placer gold , economics of a project can definitely be affected.