Oxystibiomicrolite is a rare antimony calcium tantalum oxide, typically greenish white to white. It was approved as a distinct mineral species in 1938. It was first described from Varuträsk pegmatite, 15 km northwest of Skellefteå, Västerbotten, Sweden.
Is this oxystibiomicrolite?
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 oxystibiomicrolite with a known reference. Oxystibiomicrolite sits at Mohs <5.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: resinous.
- 4Match the color rangeCompare against the expected color range: greenish white, white.
- 5Look at form & habitCrystal system: cubic. Typical habit: octahedral crystals.
Often confused with
Oxystibiomicrolite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Oxystibiomicrolite leaves white, Stibiconite leaves light yellow; luster reads resinous on Oxystibiomicrolite and pearly, opaline, glassy to earthy on Stibiconite.
How to tell apart: Streak differs, so Oxystibiomicrolite leaves white, Pyrochlore leaves brown; luster reads resinous on Oxystibiomicrolite and vitreous to resinous on Pyrochlore.
Often found alongside oxystibiomicrolite
Minerals reported to co-occur with oxystibiomicrolite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (Sb³⁺,Ca)₂Ta₂O₆O
- Mohs hardness
- <5.5
- Density
- 5.84-6.22 g/cm³
- Colors
- Streak
- White
- Luster
- Resinous
- Transparency
- Semitransparent
- Crystal system
- Cubic
- Crystal habit
- Octahedral crystals
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A very rare mineral, replacing stibiotantalite, in the lithium-rich albite unit of a complex granite pegmatite (Varuträsk pegmatite, Sweden)
Where rockhounds find oxystibiomicrolite
Classic worldwide localities
- Varuträsk pegmatite, 15 km northwest of Skellefteå, Västerbotten, Sweden
- Reported at the Odd West pegmatite, southeastern Manitoba, Canada
Field-hunting tip
Where it forms: A very rare mineral, replacing stibiotantalite, in the lithium-rich albite unit of a complex granite pegmatite (Varuträsk pegmatite, Sweden). If you start seeing stibiotantalite, antimony, allemontite in float, you are in the right ground. Typical habit: octahedral crystals. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify oxystibiomicrolite?+
Where is oxystibiomicrolite found?+
Is oxystibiomicrolite safe to handle?+
What rocks look like oxystibiomicrolite?+
What minerals are found with oxystibiomicrolite?+
What kind of rock does oxystibiomicrolite form in?+
What is oxystibiomicrolite used for?+
Find oxystibiomicrolite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
