I'm using then like a melting dish it's all I had on hand to test small samples I use the crucible as a safety to catch boil over. It all failed Now I'm grinding all the failed cupels and a crucible to see if there's any gold. I'm not using any collector metal just powdered concentrate and flux. I've made a lot of gold buttons this same way there only good for one heat cycle.
Ok. The use of Borax puzzled me.
The puzzle was that if you were cupeling, Borax did not belong.
Did you roast the sulfides prior to smelting? Are you going after the Silver in the Galena?
This is cleanup from our place in northern California not the Nevada ore. I still need to crush the rest of the Nevada samples before I decide. I'm roasting our ore samples as part of my sampling routine.
Your right you don't want the cupel glazed to work properly when cupeling.The puzzle was that if you were cupeling, Borax did not belong.
But since you were not, it is no more a puzzle
![Penagic Pens, P-223A, Gel Pens Fine Point [0.5mm] Black Ink, Roller Ballpoint Pens Matt Design, Stationery Pens for School Office Supplies](https://m.media-amazon.com/images/I/41nT+Qatb3L._SL500_.jpg)
