Greenwoodite is a rare barium vanadium iron silicate that forms black semi-prismatic to tabular grains. It was approved as a distinct mineral species in 2010. It was first described from Wigwam deposit, Akolkolex River area, southeast of Revelstoke, British Columbia, Canada.
Is this greenwoodite?
4-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch greenwoodite with a known reference. Greenwoodite sits at Mohs 5, softer than the next harder reference, harder than the previous one.
- 2Read the lusterHold the specimen under a strong light. Luster: semi-metallic, dull.
- 3Match the color rangeCompare against the expected color range: black.
- 4Look at form & habitCrystal system: trigonal. Typical habit: semi-prismatic to tabular grains.
Often confused with
Greenwoodite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Greenwoodite is noticeably harder (Mohs 5 vs. 2.5-3); luster reads semi-metallic, dull on Greenwoodite and adamantine on Crocoite.
How to tell apart: Fayalite is the harder of the two (Mohs 6.5-7 vs. 5); luster reads semi-metallic, dull on Greenwoodite and vitreous to resinous on fractures on Fayalite.
Often found alongside greenwoodite
Minerals reported to co-occur with greenwoodite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Ba₂₋ₓ(V³⁺OH)ₓV³⁺₉(Fe³⁺,Fe²⁺)₂Si₂O₂₂
- Mohs hardness
- 5
- Density
- 4.81 g/cm³
- Colors
- Luster
- Semi-metallic, dull
- Transparency
- Opaque
- Crystal system
- Trigonal
- Crystal habit
- Semi-prismatic to tabular grains
- Cleavage
- Perfect on {001}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Part of the prograde assemblage in a green schist facies metamorphosed Mississippi-Valley type base-metal deposit
Where rockhounds find greenwoodite
Classic worldwide localities
- Wigwam deposit, Akolkolex River area, southeast of Revelstoke, British Columbia, Canada
Field-hunting tip
Where it forms: Part of the prograde assemblage in a green schist facies metamorphosed Mississippi-Valley type base-metal deposit. If you start seeing quartz, celsian, apatite in float, you are in the right ground. Typical habit: semi-prismatic to tabular grains. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify greenwoodite?+
Where is greenwoodite found?+
Is greenwoodite safe to handle?+
What rocks look like greenwoodite?+
What minerals are found with greenwoodite?+
What kind of rock does greenwoodite form in?+
What is greenwoodite used for?+
Find greenwoodite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
