HTPatch said:, I have a bucket of copper nitrate
Patch,
I save my copper nitrate to use an an electrolyte for sterling silver. Dilute/concentrate the copper nitrate solution to 6M (moles per liter) or less and use a graphite cathode and anode. Plate out the copper sponge until the solution is an very light blue color and then switch out the positive lead with a sterling silver one. Bag the anode to catch and PGMs or gold that may have made it into your sterling scrap (ie: gold or rhodium plating). The copper will plate out as a moss. Periodically you will need to dip out the moss so it does not fall off the cathode and end up in the solution. The silver will saturated the solution and remain in the bottom of the cell or in solution.
You can also dehydrate the copper nitrate solution and decompose it into NO2 and Copper oxide at relatively low temperatures (less than 150C). The NO2 can be bubbled into water to form nitric acid or into a basic solution to form sodium nitrate which can be used in poor man's AR or nitric.
Steve