Glaucocerinite is a rare zinc-copper sulfate mineral typically found as secondary crusts or delicate platy aggregates in oxidized base-metal deposits. It is most famous for its occurrence in the historical mining district of Laurion, where it forms small, eye-catching blue coatings on other secondary minerals.
Is this glaucocerinite?
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 glaucocerinite with a known reference. Glaucocerinite sits at Mohs 2, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Glaucocerinite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Glaucocerinite typically shows a pearly luster.
- 4Match the color rangeCompare against the expected color range: pale blue, sky blue, bluish white.
- 5Look at form & habitCrystal system: trigonal. Typical habit: platy crystals, crusts, lamellar aggregates.
Often confused with
Glaucocerinite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside glaucocerinite
Minerals reported to co-occur with glaucocerinite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (Zn,Cu)₆Al₃(SO₄,CO₃)₂(OH)₁₈·12H₂O
- Mohs hardness
- 2
- Density
- 2.7 g/cm³
- Streak
- White
- Luster
- Pearly
- Transparency
- Translucent
- Crystal system
- Trigonal
- Crystal habit
- Platy Crystals, Crusts, Lamellar Aggregates
- Cleavage
- Perfect On {0001}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Oxidized Ore Deposits in Carbonate Rocks
- Typical price
- $20-150 for micro-mounts or small thumbnails
Where rockhounds find glaucocerinite
Classic worldwide localities
- Laurion, Greece
- Tsumeb, Namibia
- Broken Hill, Australia
Field-hunting tip
Look in oxidized ore deposits in carbonate rocks country, the host setting where glaucocerinite typically forms. If you start seeing smithsonite, azurite, malachite in float, you are in the right ground. Field specimens usually show a platy crystals, crusts, lamellar aggregates habit, so train your eye for that shape before scanning the outcrop.








