Dissolving gold. Hiding gold around WW2 (4:15 into vid) [youtube]http://www.youtube.com/watch?v=iwnKU89CCdI[/youtube]
Interesting story about the dissolved Nobel Prize medals. I wonder how hard it is the reconstitute the gold?
Just drop in any metal that's higher in the reactivity series than gold...which is all of them. Put in a peice of iron, copper, what have you, and the chloride will latch onto the more reactive metal leaving the gold to precipitate out. I was at a mine where guy accidentially dropped his steel watch into a leach tank onto a screen. When they finally got it out at the end of the shift... he had a gold plated watch