Getting rid of surplus ferrous sulfate

[elfixx]

I tryed ferous sulfate for the first time today. I added the sulfate to the AR to precipitate the gold and there is a lot of undisolved coperas left with the precipitated gold. How can I get rid of it?

 

[lazersteve]

Water.

 

[Harold_V]

Yep, what Steve said. Rinse the gold with water. The ferrous sulfate will dissolve. Add a few drops of HCl as well, which will insure that none of the ferrous sulfate precipitates as rust. Wash the gold well, using an acceptable washing procedure after you've eliminated the ferrous sulfate.

Next time, use an ounce of ferrous sulfate crystals for each ounce of gold you expect to recover. A small overage is acceptable. Dissolve the crystals in water, stirring until it is fully dissolved, then add a few drops of HCl. You'll notice the solution shifts color slightly, and comes very clear with the addition of the HCl. If it is not very clear, filter to eliminate flocculence. Pour the solution in your gold chloride. Test to insure all gold has been precipitated. If not, add more ferrous sulfate solution.

Harold