However it's spelled, Orpiment is expensive on there. And I know galena is lead-based, but the others I didn't realise. And yes, I did say it in jest, as it is the most 'without thinking too hard' dangerous mineral I know.I think you said that in jest - but a lot of people buy gemstones for their beauty and don't know much about them.
Gem Collector have a stone called 'Orpiment' (they spell it, incorrectly, as 'Orphiment').
Orpiment IS asbestos!
Gem Collector sell it in faceted form - meaning some people that like the look of it could set it into a ring or pendant, not knowing that they're setting asbestos.
It's surprising how many toxic stones there are out there (many are safe though until they're ingested as dust).
Galena
Cinnabar
Malachite
Chalcopyrite
Chrysocolla
The most they're likely to do to a human is cause a bit of stomach upset - but if someone was to handle them and then play with one of their pets, etc, then they could potentially be fatal to an animal - particularly Cinnabar or Galena.