Iseite is a rare manganese molybdenum oxide that forms iron-black poorly-formed crystals. Associated minerals include rhodochrosite, powellite and molybdenite. It was first described from Shobu Fe-Mn deposit, near Ise City, Mie Prefecture, Japan.
Is this iseite?
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 iseite with a known reference. Iseite sits at Mohs 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: iron-black.
- 5Look at form & habitCrystal system: hexagonal. Typical habit: poorly-formed crystals.
Often confused with
Iseite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside iseite
Minerals reported to co-occur with iseite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Mn₂Mo₃O₈
- Mohs hardness
- 4-5
- Density
- 5.85 g/cm³
- Colors
- Streak
- Black
- Luster
- Submetallic
- Transparency
- Opaque
- Crystal system
- Hexagonal
- Crystal habit
- Poorly-formed crystals
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In a stratiform ferro-manganese deposit, embedded in chert and closely associated with limestone and greenstone in an accretionary complex
Where rockhounds find iseite
Classic worldwide localities
- Shobu Fe-Mn deposit, near Ise City, Mie Prefecture, Japan
Field-hunting tip
Where it forms: In a stratiform ferro-manganese deposit, embedded in chert and closely associated with limestone and greenstone in an accretionary complex. If you start seeing rhodochrosite, powellite, molybdenite in float, you are in the right ground. Typical habit: poorly-formed crystals. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify iseite?+
Where is iseite found?+
What rocks look like iseite?+
What minerals are found with iseite?+
What kind of rock does iseite form in?+
What is iseite used for?+
Find iseite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
