BTW- just checked the Idaho Geological Survey report. Cu is mentioned in the analytical section where they were measuring amounts of metals in water and waste piles, but is not really sginificant. There is no mention of Cu in the rest of the report where the history of the mines is discussed. If Cu is present, is wasn't economically significant enough to have been mentioned in the historical accounts.

Sphindog- I also saw the stuff coming off the table at the mill. The gold stream seemed to be a mix of colors- some of the typical gold color, some a little more orangish, as if it were an alloy of gold/copper. Doesn't take much copper to affect the color. Really hard to say, though- if the particles are small enough you get into the range where color is also affected by particle size. If gold particles are small enough (colloidal or nano particles), it can actually be purple!