Comparison · Sulfide Minerals vs Vanadate Minerals
Orpiment vs Vanadinite
Orpiment and Vanadinite are easy to confuse. Vanadinite is harder (Mohs 3) than Orpiment (Mohs 1.75), so Vanadinite will scratch Orpiment and not the other way round. A fingernail (Mohs 2.5) scratches it easily. Below is a side-by-side comparison of their properties and the quick tests that separate them.
Key differences between Orpiment and Vanadinite
- Vanadinite is harder (Mohs 3) than Orpiment (Mohs 1.75), so Vanadinite will scratch Orpiment and not the other way round. A fingernail (Mohs 2.5) scratches it easily.
- Streak color differs: Orpiment leaves a pale lemon yellow streak on unglazed porcelain, Vanadinite leaves brownish yellow.
- Vanadinite feels noticeably heavier for its size (specific gravity 6.9 versus 3.49 for Orpiment).
- They overlap in yellow, orange, and brown, but Vanadinite also comes in red.
- Well-formed crystals give it away: Orpiment is monoclinic, Vanadinite is hexagonal.
Orpiment vs Vanadinite properties
| Property | Orpiment | Vanadinite |
|---|---|---|
| Type | Sulfide Minerals | Vanadate Minerals |
| Mohs hardness | 1.75 | 3 |
| Luster | resinous | resinous |
| Streak | Pale lemon yellow | Brownish yellow |
| Transparency | translucent | translucent |
| Specific gravity | 3.49 | 6.9 |
| Crystal system | monoclinic | hexagonal |
| Common colors | Lemon yellow, Golden yellow, Orange-yellow, Brownish yellow | Red, Orange, Brown, Yellow |
| Rarity | uncommon | uncommon |
| Typical specimen value | $10–$400+ | $10–$500+ |
Which is more valuable?
Typical specimens of Orpiment and Vanadinite trade in a similar range, around $60.
About Orpiment
Orpiment is a soft arsenic sulfide mineral famous for its brilliant lemon to golden-yellow color and resinous luster. It forms in low-temperature veins and hot spring deposits, commonly alongside red-orange realgar.
About Vanadinite
Vanadinite is a lead chlorovanadate famous for its brilliant red to orange hexagonal crystals. A heavy, secondary mineral of oxidized lead deposits, it is highly sought by collectors and serves as an ore of both vanadium and lead.
Orpiment vs Vanadinite FAQ
Is Orpiment the same as Vanadinite?
No. Orpiment is a sulfide mineral while Vanadinite is a vanadate mineral. Vanadinite is harder (Mohs 3) than Orpiment (Mohs 1.75), so Vanadinite will scratch Orpiment and not the other way round. A fingernail (Mohs 2.5) scratches it easily.
How can you tell Orpiment from Vanadinite?
Vanadinite is harder (Mohs 3) than Orpiment (Mohs 1.75), so Vanadinite will scratch Orpiment and not the other way round. A fingernail (Mohs 2.5) scratches it easily. Streak color differs: Orpiment leaves a pale lemon yellow streak on unglazed porcelain, Vanadinite leaves brownish yellow. Vanadinite feels noticeably heavier for its size (specific gravity 6.9 versus 3.49 for Orpiment).
Which is harder, Orpiment or Vanadinite?
Vanadinite is harder: Mohs 3 against Mohs 1.75 for Orpiment.
Which is more valuable, Orpiment or Vanadinite?
Typical specimens of Orpiment and Vanadinite trade in a similar range, around $60.
