Tokyoite is a rare barium manganese vanadate that typically forms as small, attractive tabular crystals in oxidized manganese deposits. It is most recognized for its characteristic yellow-green color and is highly prized by systematic mineral collectors. Due to its arsenic content, it should be handled with standard precautions and stored carefully.
Is this tokyoite?
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 tokyoite with a known reference. Tokyoite 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: dark brownish red.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: reddish black.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: irregular grains.
Often confused with
Tokyoite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Tokyoite leaves dark brownish red, Tsumcorite leaves yellow.
How to tell apart: Streak differs, so Tokyoite leaves dark brownish red, Hidalgoite leaves white; luster reads vitreous on Tokyoite and dull in aggregates on Hidalgoite.
How to tell apart: Streak differs, so Tokyoite leaves dark brownish red, Bayldonite leaves green; luster reads vitreous on Tokyoite and resinous on Bayldonite.
Often found alongside tokyoite
Minerals reported to co-occur with tokyoite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Ba₂Mn³⁺(VO₄)₂(OH)
- Mohs hardness
- 4-4.5
- Density
- 4.62 g/cm³
- Colors
- Streak
- Dark brownish red
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Irregular grains
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- From an outcrop, in an abandoned Mn deposit in brecciated braunite and in veinlets in chert blocks enclosed in sandstone in an accretionary complex
Where rockhounds find tokyoite
Classic worldwide localities
- Shiromaru mine, Okutama Town, Tokyo, Japan
Field-hunting tip
Where it forms: From an outcrop, in an abandoned Mn deposit in brecciated braunite and in veinlets in chert blocks enclosed in sandstone in an accretionary complex. If you start seeing braunite, hyalophane, tamaite in float, you are in the right ground. Typical habit: irregular grains. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify tokyoite?+
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Find tokyoite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
