re: #416 Political Atheist

I thought that looked way past gold temps. Induction furnaces are excellent heat. Controllable and powerful. Platinum crucible? Or platinum in a ceramic? 1700 C is close to the flow point for pt. I have seen those pt crucibles from labs that grow gems.

Platinum crucible. It is very close to the flow point, but it’s also pushing that furnace to get to that temp, so I don’t worry about it going over. When it’s pulled out, though, the wire holding it to the hook has stretched into a triangle, as opposed to a hoop.

We never did get the 1800 deg furnace set up while I was there, but that was ok, because 1700 was the top of what I needed. I very rarely had corundum show up in samples (when making a glass, this is bad - want no crystals at all), generally because I was pushing the aluminum content too far. Of course, the more aluminum you have, the higher the melting point (hence the high temperatures).

This is the relating-to-the-rest-of-my-life reason why my engagement/wedding rings are platinum with sapphire (and a few small diamonds).