Help: white gold ring prongs break

Cast white gold becomes brittle if quenched too early. After casting it should cool down slowly without quenching the flask then you have to leave the flask sit in water to soften the investment to dig out the gold. You will never have prongs breaking on you again.

Vasken

Hi Vasken, I’m not disagreeing with you, Just expanding on your thoughts a little. I’ve been told exactly the same thing over the years. But I’ve also been told something contradictory by a couple of different casters in manufacturing facilities. They agreed not to quench white gold after soldering otherwise the piece could become brittle. But they said when casting to wait until the button is no longer red in a darkened room, then quench. So it’s still hot at that point. They felt like leaving to cool fully had negative effects, something to do with the insulating effect of the investment. It’s interesting.

That’s what I do. Wait a little but quench the flask when hot and I never have any brittleness. But I have friends who do as you suggest and they never have brittleness either. I’ve come to believe that may have something to do with modern metallurgy creating more forgiving alloys than what we all used to use?

I think an area where variables are more likely to give you all sorts of negative results are flask and metal temps when casting. There you’ve got to find the sweet spot and stick to it.

Another interesting thing I was told was that the problem with white gold is that the whitening agent (usually nickel) is not soluble with gold. But the other ingredients in the alloy are and nickel is soluble with those ingredients as well. So on a microscopic level you have nickel rich boundaries. These are where you have the brittleness issues. These areas are also subject to corrosion of a sort from chlorine and the like. So it’s not just quenching but excessive exposure to bleach in dish water or hot tubs, etc, that can cause brittleness. That’s what I was told anyway. Food for thought.
Mark