investment casting
A molding process whereby precious metals are melted down and formed into household items, sporting-goods, etc., enabling their buyers to be less "obvious" or "visible" in their acquisition of said valuable minerals than they would be if they simply purchased coins, bars, etc.
Two excellent examples of investment casting would be electrical/plumbing components and golf clubs, which can be formed from gold, silver, platinum, etc. and installed/stored in the investor's home without anyone's being the wiser.