Bassoite is a rare vanadium mineral found primarily in specific manganese-iron deposits in the Brosso mine in Italy. It typically appears as small, thin tabular crystals or delicate crusts and is highly sought after by advanced collectors of rare species.
Is this bassoite?
5-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 bassoite with a known reference. Bassoite sits at Mohs 4-4.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: black.
- 3Read the lusterHold the specimen under a strong light. Luster: submetallic.
- 4Match the color rangeCompare against the expected color range: black.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: tabular crystals, aggregates.
Often confused with
Bassoite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Bassoite is noticeably harder (Mohs 4-4.5 vs. ~2.5); streak differs, so Bassoite leaves black, Pascoite leaves cadmium-yellow; luster reads submetallic on Bassoite and vitreous to subadamantine on Pascoite.
How to tell apart: Bassoite is noticeably harder (Mohs 4-4.5 vs. ~2); streak differs, so Bassoite leaves black, Sherwoodite leaves pale blue; luster reads submetallic on Bassoite and vitreous to earthy on Sherwoodite.
Often found alongside bassoite
Minerals reported to co-occur with bassoite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- SrV₃O₇·4H₂O
- Mohs hardness
- 4-4.5
- Density
- 2.940 g/cm³
- Colors
- Streak
- Black
- Luster
- Submetallic
- Transparency
- Opaque
- Crystal system
- Monoclinic
- Crystal habit
- Tabular crystals, aggregates
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In a metamorphosed bedded chert and Mn ore deposit
Where rockhounds find bassoite
Classic worldwide localities
- Molinello manganese mine, Val Graveglia, eastern Liguria, northern Apennines, Italy
Field-hunting tip
Where it forms: In a metamorphosed bedded chert and Mn ore deposit. If you start seeing rhodonite, quartz, braunite in float, you are in the right ground. Typical habit: tabular crystals, aggregates. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify bassoite?+
Where is bassoite found?+
Is bassoite safe to handle?+
What rocks look like bassoite?+
What minerals are found with bassoite?+
What kind of rock does bassoite form in?+
What is bassoite used for?+
Find bassoite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
