Sibirskite is a rare calcium borate mineral typically found in metamorphosed carbonate rocks associated with skarn deposits. It usually occurs as small, white to colorless platy or fibrous crystalline aggregates. It is primarily a collector's mineral known from the Tayozhnoye iron ore deposit in the Sakha Republic of Russia.
Is this sibirskite?
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 sibirskite with a known reference. Sibirskite sits at Mohs 3-4 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Sibirskite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Sibirskite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: white, colorless, gray.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: platy or fibrous aggregates.
Often confused with
Sibirskite vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside sibirskite
Minerals reported to co-occur with sibirskite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- CaHB₂O₅
- Mohs hardness
- 3-4
- Density
- 2.98 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Monoclinic
- Crystal habit
- Platy or Fibrous Aggregates
- Cleavage
- Good
- Rarity
- Rare
- Uses
- Collector, Research
- Host rock
- Skarn Deposits
- Typical price
- expensive due to rarity
Where rockhounds find sibirskite
Classic worldwide localities
- Tayozhnoye iron deposit, Russia
- Siberia, Russia
Field-hunting tip
Look in skarn deposits country — that is the host setting where sibirskite typically forms. If you start seeing magnetite, ludwigite, calcite in float, you are in the right ground. Field specimens usually show a platy or fibrous aggregates habit, so train your eye for that shape before scanning the outcrop.






