archeonist said:
Hi guys, last week I processed some fingers using Lazersteve's method with AP. It was a small batch, only 70 grams of close cut fingers, just to see if I understand the process. Everything went well, the fingers came off and when I collected them it looked very promesing. Dissolved the foils in AR, this went well too. Finally precipitated using SMB, went also very well. After one day I collected the powder and after drying I got no more gold than only 0,17 grams. Is this a normal yield?
Depending on the fingers, the thickness of the Au, how much of the surface area is actually covered in Au, etc.
If we can accept the following figures
about 2 grams of Au per lb of close cut fingers
about 453.5 grams in a lb
Then we can divide the average 2 grams of Au per lb but the number of grams in a lb to get a figure of about how much Au there is per gram
2/453.5 = 0.0044101433296582
Now we can take this number and multiply it by the grams you processed
0.0044101433296582 x 70 = .0.308710033076075 or for argument sake, you should have around .3 grams for your effort.
That's a little more than what you extracted, so, for argument sake again, we figure your fingers at 1 gram per lb, you would yield .15+
So to answer your question, you are within the lower ranger of yield, not the lowest. If I had to guess I would say your finger boards are from between 2000 and 2006. Where your fingerboards newer, shiny, on green board?
Scott