Mariinskite is an extremely rare beryllium-chromium oxide mineral discovered in the Mariinskoye emerald deposit of the Ural Mountains. It is structurally related to chrysoberyl and is prized by advanced collectors for its intense green color and unique chemical composition. Due to its scarcity and typical microscopic grain size, it is almost exclusively found in scientific research collections or held by specialized mineral curators.
Is this mariinskite?
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 mariinskite with a known reference. Mariinskite sits at Mohs 8.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Mariinskite leaves a pale green streak.
- 3Read the lusterHold the specimen under a strong light. Mariinskite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: green, emerald-green.
- 5Look at form & habitCrystal system: orthorhombic. Typical habit: anhedral grains.
Often confused with
Mariinskite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Mariinskite leaves pale green, Chrysoberyl leaves white.
How to tell apart: Streak differs, so Mariinskite leaves pale green, Alexandrite leaves white.
How to tell apart: Mariinskite is noticeably harder (Mohs 8.5 vs. 6.5-7.5); streak differs, so Mariinskite leaves pale green, Uvarovite leaves white.
Often found alongside mariinskite
Minerals reported to co-occur with mariinskite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- BeCr₂O₄
- Mohs hardness
- 8.5
- Density
- 4.25 g/cm³
- Colors
- Streak
- Pale Green
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Orthorhombic
- Crystal habit
- Anhedral Grains
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector, Scientific Research
- Host rock
- Phlogopite-rich Mica Schists
Where rockhounds find mariinskite
Classic worldwide localities
- Mariinskoye emerald deposit, Ural Mountains, Russia
Field-hunting tip
Look in phlogopite-rich mica schists country, the host setting where mariinskite typically forms. If you start seeing chrysoberyl, alexandrite, phlogopite in float, you are in the right ground. Field specimens usually show a anhedral grains habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify mariinskite?+
Where is mariinskite found?+
What rocks look like mariinskite?+
What minerals are found with mariinskite?+
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Find mariinskite on the map
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