I have used the salt system if it is the same one you are talking
about there are lots of noxious fumes I actually got blisters in my
throat from doing it and had chemical burns on my hands, send it out
to a refiner. I was doing this at my first jewelery job and had no
clue as to what was going on and neither did the owner he spent
three days in the hospital he scarred his lungs. Dont want to scare
you but be real careful.