Gene Kearns wrote:

I thought drywall was principally gypsum and quartz.....

Drywall is gypsum plaster between two layers of thick paper. The
taping/finishing compound is something else. Just read the label on the USG
stuff I use. Limestone, water, talc (Ron's right, as usual), mica, and vinyl
acetate polymer.

The reason I thought the talc had been removed is that in the mid-80s the cans
used to have a warning label that the compound contained talc. The label
disappeared in the 90s, so I thought the talc was gone too.

George Patterson
He who tries to carry a cat by the tail learns something he can learn in
no other way.