Colored gold alloys (was Black gold)

I was doing some research myself on colored alloys. I found a very
interesting document that may make a good read for people on the
list.

http://www.gold.org/Indu/GBull/1999_4/Cretu.pdf

It discusses black gold, blue gold, purple gold, etc. It’s got
pictures too, for those of us who haven’t seen purple gold and read
only text descriptions.

Particularly interesting is the scientific discussion of how the
alloys get their color!

  • darcy