How to extract very fine powder gold out of black rock

I have several rocks that have very fine powder gold in them what is the best way to extract out the gold as I have crushed one up and placed powdered rock in a pan but it is so fine how do I separate it from the black host rock powder as it is very very fine:bounce: 

This is a very inexperienced opinion, but I would either let the black send be eaten way by HC acid (brick acid), and pan the remnants.
or use mercury to create an amalgam with gold and put that through a retort. But this is book knowledge, there are a lot of safety issues with both methods I think...

Gold Dreamer wrote:
or use mercury to create an amalgam with gold and put that through a retort.

     Or use a big spud, cut in hlf and scoop out a hollow to fit ya amalgam ball, wrap in foil ten times and burn the crap outta it in the fire coals..... Gold button ready for sale.

J

just use the blue bowl