[COFF] Re: Typical Fate of Older Hardware

[Paul Winalski <paul.winalski@gmail.com>]

Brad Spencer is right about the resistance of gold to attack by acids
makes using acids to attack the substrate an effective strategy.

One other interesting property of gold is that it dissolves in liquid
mercury.  One old and primitive--but effective--way to extract gold is
to grind the ore finely, mix it with liquid mercury, then allow the
substrate to settle out.  You then have liquid mercury with gold
dissolved in it.  You heat the mercury to evaporate it away and
there's your gold.  The problem with this method is of course the
extreme toxicity and volatility of liquid mercury.  It's difficult
(and expensive) to handle it safely, and in those parts of the world
where this method is still in use, it usually isn't handled safely.
The mercury-contaminated waste left over after the extraction is also
toxic and environmentally damaging to dispose of.

-Paul W.