nitric turned a dark rust color

[Geo]

im sure i does degrade the dish but i want to be able to see the bottom of the dish before i start to melt. in my way of thinking, a melting dish has only a certain number of uses and preserving resources is economically sound business and the small loss of use of the dish is better than replacing the whole dish.

 

[Harold_V]

a melting dish has only a certain number of uses and preserving resources is economically sound business and the small loss of use of the dish is better than replacing the whole dish.

That was my philosophy, too. While the soda ash and borax process does a good job of cleaning a dish, it's quite hard on its longevity. The soda ash does what it does best---it dissolves silica, so clay dished are thinned quite readily by that method. On the positive side, I never failed to recover a button of alloy from the process. It was always worth more than the dish. Armed with that thought, when you're finished cleaning one with sulfuric, might be a good idea to send the solution, solids and all, to the stock pot.

Harold