glazenerd

Marcia: 

sulfur melts at low temperatures and vaporize well below bisq temps. The problem is that  sulfur anions bond with almost every other element. In our case iron: ferrous sulfide. Once that bond takes place, which occurs below bisq temps: that bond creates an impermeable barrier that the off gassing of spars and carbons cannot  penetrate. This chain reaction is the basis of bloating. The question is: at what level of sulfides?

in my foil saggars. I use a lot of them. PS I found my crystalline glaze thesis written on a type writer in 1973. Want a copy? I can scan and send you via email. Pls remember it was written almost half a century ago about work done a half century prior to that. maybe I should read it first. 

it discusses temp. for various crystal shapes, limit formulas etc.