Hloušekite is a rare nickel-cobalt arsenide mineral found in association with uraninite-bearing hydrothermal veins. It typically presents as microscopic grains or small aggregates and is primarily identified via chemical analysis in a laboratory setting due to its similarity to other nickel-cobalt minerals.
Is this hloušekite?
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 hloušekite with a known reference. Hloušekite sits at Mohs 2-3, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: grayish white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: pale green.
- 5Look at form & habitCrystal system: triclinic. Typical habit: anhedral grains, aggregates.
Often confused with
Hloušekite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Gersdorffite is the harder of the two (Mohs 5.5 vs. 2-3); luster reads vitreous on Hloušekite and metallic on Gersdorffite.
How to tell apart: Cobaltite is the harder of the two (Mohs 5.5 vs. 2-3); luster reads vitreous on Hloušekite and metallic on Cobaltite.
How to tell apart: Skutterudite is the harder of the two (Mohs 5.5-6 vs. 2-3); streak differs, so Hloušekite leaves grayish white, Skutterudite leaves black; luster reads vitreous on Hloušekite and metallic on Skutterudite.
Often found alongside hloušekite
Minerals reported to co-occur with hloušekite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- NiCu₄(AsO₄)₂(AsO₃OH)₂(H₂O)₈·H₂O
- Mohs hardness
- 2-3
- Density
- 3.295 g/cm³
- Colors
- Streak
- Grayish white
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Triclinic
- Crystal habit
- Anhedral grains, aggregates
- Cleavage
- Perfect on {010}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A secondary mineral derived from highly-oxidized, hydrothermal quartz veins containing disseminated tennantite, chalcopyrite, and Ni-Co-arsenides
Where rockhounds find hloušekite
Classic worldwide localities
- Geister vein, third Geister level in the Rovnost (formerly Werner) mine, Jáchymov (St Joachimsthal), Western Bohemia, Czech Republic
Field-hunting tip
Where it forms: A secondary mineral derived from highly-oxidized, hydrothermal quartz veins containing disseminated tennantite, chalcopyrite, and Ni-Co-arsenides. If you start seeing veselovskýite, pradetite, lavendulan in float, you are in the right ground. Typical habit: anhedral grains, aggregates. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify hloušekite?+
Where is hloušekite found?+
Is hloušekite safe to handle?+
What rocks look like hloušekite?+
What minerals are found with hloušekite?+
What kind of rock does hloušekite form in?+
What is hloušekite used for?+
Find hloušekite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
