Clinoungemachite is a rare potassium sodium iron sulfate that forms colorless to pale yellow as minute thick tabular pseudorhombohedral crystals. It was approved as a distinct mineral species in 1938. It was first described from Chuquicamata, Antofagasta, Chile.
Is this clinoungemachite?
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 clinoungemachite with a known reference. Clinoungemachite sits at Mohs 2.5-3, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: colorless, white, light yellow.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: as minute thick tabular pseudorhombohedral crystals.
Often confused with
Clinoungemachite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside clinoungemachite
Minerals reported to co-occur with clinoungemachite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- K₃Na₈Fe³⁺(SO₄)₆(OH)₂·10H₂O
- Mohs hardness
- 2.5-3
- Density
- 6.8-7.2 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Monoclinic
- Crystal habit
- As minute thick tabular pseudorhombohedral crystals
- Cleavage
- Perfect
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Very rarely formed by the oxidation of pyrite in an arid climate, in veins and cavities in other massive iron sulfates
Where rockhounds find clinoungemachite
Classic worldwide localities
- Chuquicamata, Antofagasta, Chile
Field-hunting tip
Where it forms: Very rarely formed by the oxidation of pyrite in an arid climate, in veins and cavities in other massive iron sulfates. If you start seeing ungemachite, jarosite, sideronatrite in float, you are in the right ground. Typical habit: as minute thick tabular pseudorhombohedral crystals. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify clinoungemachite?+
Where is clinoungemachite found?+
What rocks look like clinoungemachite?+
What minerals are found with clinoungemachite?+
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What is clinoungemachite used for?+
Find clinoungemachite on the map
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