Tomichite is a very rare titanium-vanadium-arsenic mineral found primarily in specific metasomatized ultramafic rocks in Western Australia. It typically occurs as small, dark, platy crystals that resemble ilmenite or hematite, often requiring X-ray diffraction for definitive identification in the field.
Is this tomichite?
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 tomichite with a known reference. Tomichite sits at Mohs 5-6 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Tomichite leaves a brown streak.
- 3Read the lusterHold the specimen under a strong light. Tomichite typically shows a submetallic luster.
- 4Match the color rangeCompare against the expected color range: dark brown, black.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: platy crystals, granular aggregates.
Often confused with
Tomichite vs. its common look-alikes — and how to tell them apart in the field.
How to tell apart: Streak differs — Tomichite leaves brown, Manaccanite leaves black.

How to tell apart: Streak differs — Tomichite leaves brown, Iron Ore leaves reddish-brown to black; luster reads submetallic on Tomichite and metallic to submetallic on Iron Ore.
Often found alongside tomichite
Minerals reported to co-occur with tomichite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Ti₄V₃AsO₁₃(OH)₆
- Mohs hardness
- 5-6
- Density
- 4.8-5.0 g/cm³
- Colors
- Streak
- Brown
- Luster
- Submetallic
- Transparency
- Opaque
- Crystal system
- Monoclinic
- Crystal habit
- Platy Crystals, Granular Aggregates
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Metasomatized Ultramafic Rocks
- Typical price
- $50-300 per small specimen
Where rockhounds find tomichite
Classic worldwide localities
- Mount Tomich, Australia
Field-hunting tip
Look in metasomatized ultramafic rocks country — that is the host setting where tomichite typically forms. If you start seeing ilmenite, hematite, quartz in float, you are in the right ground. Field specimens usually show a platy crystals, granular aggregates habit, so train your eye for that shape before scanning the outcrop.


