Dear Alan, Your problem seem to be for so many other artificers like
us, as the main desperate casting and fabricating problem for white
gold.
I would suggest to contact LacyWest Supplies, Vancouver, Canada,
and ask them about the Italian White Alloy: Italian White alloy -
This is the alloy we recommend for casting and fabricating 10K to
18K white gold. If you are casting only, that is, you will not be
rolling or fabricating after you alloy the white gold, a most viable
alternative is our # 915 10-18K White Casting Alloy. Specifications
and instructions for the #915 alloy are here:
http://www.lacywest.com/alloy915.htm
Hope that you find the help you are after.
JOSEPH TANTI, MALTA EUROPE
http://jostanti.cjb.com