Hutchinsonite is one of the few crystallized THALLIUM-containing minerals that has macro-crystals. It is very rare, and in this quality has occurred fomr just several sporadic finds at the orpiment mines in Peru. This style dates back at least before the 90s, as it was old even when I found out what it was and started to buy every one that came my way. This piece has extremely sharp crystals to 6 mm mixed in beautifully with the contrasting orpiment - and this association is what makes a piece more than just "reference," but also a fine specimen.