Cuprosklodowskite is a striking secondary uranium mineral that forms beautiful, bright green acicular or fibrous needle-like crystals. It is highly sought after by collectors for its vivid color and intense green fluorescence under UV light, though it requires specialized storage due to its radioactivity and fragility.
Is this cuprosklodowskite?
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 cuprosklodowskite with a known reference. Cuprosklodowskite 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. Cuprosklodowskite leaves a greenish yellow streak.
- 3Read the lusterHold the specimen under a strong light. Cuprosklodowskite typically shows a dull to silky luster.
- 4Match the color rangeCompare against the expected color range: grass-green, emerald-green, yellow-green.
- 5Look at form & habitCrystal system: triclinic. Typical habit: acicular or fibrous radial aggregates, crusts.
Often confused with
Cuprosklodowskite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Cuprosklodowskite leaves greenish yellow, Vandenbrandeite leaves light green; luster reads dull to silky on Cuprosklodowskite and vitreous on Vandenbrandeite.
How to tell apart: Streak differs, so Cuprosklodowskite leaves greenish yellow, Torbernite leaves pale green; luster reads dull to silky on Cuprosklodowskite and vitreous on Torbernite.
How to tell apart: Streak differs, so Cuprosklodowskite leaves greenish yellow, Autunite leaves pale yellow; luster reads dull to silky on Cuprosklodowskite and pearly on Autunite.
Often found alongside cuprosklodowskite
Minerals reported to co-occur with cuprosklodowskite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Cu(UO₂)₂(SiO₃OH)₂·6H₂O
- Mohs hardness
- 3-4
- Density
- 3.85 g/cm³
- Streak
- Greenish Yellow
- Luster
- Dull to Silky
- Transparency
- Translucent
- Crystal system
- Triclinic
- Crystal habit
- Acicular or Fibrous Radial Aggregates, Crusts
- Cleavage
- Perfect in One Direction
- Fluorescence
- Bright Green Under SW and LW UV
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Oxidized Zones of Uranium-bearing Hydrothermal Deposits
Where rockhounds find cuprosklodowskite
Classic worldwide localities
- Musonoi Mine, Democratic Republic of the Congo
- Shinkolobwe, Democratic Republic of the Congo
- Joachimsthal, Czech Republic
Field-hunting tip
Look in oxidized zones of uranium-bearing hydrothermal deposits country, the host setting where cuprosklodowskite typically forms. If you start seeing sklodowskite, kasolite, becquerelite in float, you are in the right ground. Field specimens usually show a acicular or fibrous radial aggregates, crusts habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify cuprosklodowskite?+
Where is cuprosklodowskite found?+
Is cuprosklodowskite safe to handle?+
What rocks look like cuprosklodowskite?+
What minerals are found with cuprosklodowskite?+
What kind of rock does cuprosklodowskite form in?+
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Find cuprosklodowskite on the map
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