Gold recovery from Aqua Regia Acid Use zinc powder.@MakeGold
Aqua regia is a mixture of nitric acid and hydrochloric acid, optimally in a molar ratio of 1:3. Aqua regia is a yelloworange (sometimes red) fuming liquid, so named by alchemists because it can dissolve the noble metals gold and platinum, though not all metals.
Aqua regia is primarily used to produce chloroauric acid, the electrolyte in the Wohlwill process for refining the highest quality (99.999%) gold.