Comment on Pens in Space
it hasn’t been graphite for while now either….
pencil lead
Chalk isn’t chalk?
Regular chalk is calcium carbonate. Crayola’s website says their sidewalk chalk uses calcium sulfate (gypsum as an ingredient in plaster of paris).
So they’re both calcium salts.
no
Vespair@lemm.ee 1 week ago
Chalk isn’t chalk?
Arcka@midwest.social 1 week ago
Regular chalk is calcium carbonate. Crayola’s website says their sidewalk chalk uses calcium sulfate (gypsum as an ingredient in plaster of paris).
So they’re both calcium salts.
xor@lemmy.dbzer0.com 1 week ago
no