While I stated it is not difficult to describe a process for
reducing metal salts to pure metal powders It does require some
more knowledge . For small quantities less than kilograms - buy
it. Johnson Mattey lists it in 60, 100 and 300 mesh:
http://www.chemicals.matthey.com/catalysts/viewcompound.asp?CompoundID=308
http://www.chemicals.matthey.com/products/products.asp?type=compound&typeid=13&metal=12
It won’t be cheap, but will be inexpensive compared to a process
learning curve.
There will be other suppliers but this is the largest gold
processor.
Jesse