I worked at a custom jewelry shop in college. I was told about the fantastic 10 year bonus when the carpets are torn out and incinerated.

Unfortunately I didn’t stay long enough to benefit, but I did find quite a few small diamonds when they would catch the light just right.

Seems like jewelers could be well served by working in some kind of specialized fume hood. The neighborhood jeweler I went to for an engagement ring was just grinding away in a little back room.