Bystrite is a rare member of the cancrinite group, most notable for its intense yellow color and strong fluorescence. It is primarily found in the Lake Baikal region of Russia, occurring as distinct, sometimes transparent prismatic crystals in carbonate-rich metamorphic environments.
Is this bystrite?
4-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 bystrite with a known reference. Bystrite sits at Mohs 5, softer than the next harder reference, harder than the previous one.
- 2Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 3Match the color rangeCompare against the expected color range: yellow.
- 4Look at form & habitCrystal system: trigonal. Typical habit: irregular grains, tabular.
Often confused with
Bystrite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside bystrite
Minerals reported to co-occur with bystrite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Na₇Ca(Al₆Si₆)O₂₄(S₅)Cl
- Mohs hardness
- 5
- Density
- 2.43 g/cm³
- Colors
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Trigonal
- Crystal habit
- Irregular grains, tabular
- Cleavage
- Good on {101̄0}; poor parting on {0001}
- Fluorescence
- Bright yellow under SW UV
- Rarity
- Rare
- Uses
- Collector
- Host rock
- As metasomatic lenses in dolomitic marble
Where rockhounds find bystrite
Classic worldwide localities
- Found at the Malaya Bystraya lazurite deposit, ~6 km above the confluence of Malaya Bystraya river and Lazurnyi creek, ~25 km from Sludyanka, near Lake Baikal, Eastern Siberian Region, Russia
Field-hunting tip
Where it forms: As metasomatic lenses in dolomitic marble. If you start seeing lazurite, diopside, calcite in float, you are in the right ground. Typical habit: irregular grains, tabular. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify bystrite?+
Where is bystrite found?+
What rocks look like bystrite?+
What minerals are found with bystrite?+
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Find bystrite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
