Manganostibite is a rare manganese antimonate mineral typically found in metamorphic manganese ores. It is primarily known for its distinct dark reddish-brown color and submetallic luster, usually occurring in small granular masses or tabular crystals within skarn environments.
Is this manganostibite?
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 manganostibite with a known reference. Manganostibite sits at Mohs 3.5-4, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: chocolate-brown.
- 3Read the lusterHold the specimen under a strong light. Luster: greasy.
- 4Match the color rangeCompare against the expected color range: black.
- 5Look at form & habitCrystal system: orthorhombic. Typical habit: tabular crystals, massive, granular.
Often confused with
Manganostibite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Manganostibite leaves chocolate-brown, Allactite leaves gray to faint brown; luster reads greasy on Manganostibite and vitreous, slightly greasy on fracture surfaces on Allactite.
How to tell apart: Hematite is the harder of the two (Mohs 5-6 vs. 3.5-4); streak differs, so Manganostibite leaves chocolate-brown, Hematite leaves cherry-red or reddish brown; luster reads greasy on Manganostibite and metallic or submetallic to dull on Hematite.
Often found alongside manganostibite
Minerals reported to co-occur with manganostibite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Mn₇SbAsO₁₂
- Mohs hardness
- 3.5-4
- Density
- 4.949 g/cm³
- Colors
- Streak
- Chocolate-brown
- Luster
- Greasy
- Transparency
- Opaque to slightly translucent
- Crystal system
- Orthorhombic
- Crystal habit
- Tabular crystals, massive, granular
- Cleavage
- Indistinct
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In late-stage hydrothermal veins in manganese deposits in limestone
Where rockhounds find manganostibite
Classic worldwide localities
- Moss and Brattfors mines, near Nordmark, Värmland, Sweden
Field-hunting tip
Where it forms: In late-stage hydrothermal veins in manganese deposits in limestone. If you start seeing hausmannite, sonolite, katoptrite in float, you are in the right ground. Typical habit: tabular crystals, massive, granular. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify manganostibite?+
Where is manganostibite found?+
Is manganostibite safe to handle?+
What rocks look like manganostibite?+
What minerals are found with manganostibite?+
What kind of rock does manganostibite form in?+
What is manganostibite used for?+
Find manganostibite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
