R
I'm very new to fire assaying, I've only done 6 so far. In all but one the cupel has cracked. I've read that when this happens that you will lose some of the pm's, is this correct?
I figured they were cracking because of moisture, but I leave them on the furnace during the fireing of the crucible, and put them in the furnace for about ten minutes before adding the lead, but still they crack. I'm cupeling between 1500f and 1750f. It's taking about an hour and fifteen minutes, sometimes a little less.
Could anyone give me a reason for my troubles? I appreciate any help, and don't offend easilly so don't hold back telling me if I'm doing it all wrong.
Thanks for any help
rookieminer
I figured they were cracking because of moisture, but I leave them on the furnace during the fireing of the crucible, and put them in the furnace for about ten minutes before adding the lead, but still they crack. I'm cupeling between 1500f and 1750f. It's taking about an hour and fifteen minutes, sometimes a little less.
Could anyone give me a reason for my troubles? I appreciate any help, and don't offend easilly so don't hold back telling me if I'm doing it all wrong.
Thanks for any help
rookieminer