Chlormanganokalite is a very rare potassium manganese chloride mineral typically found in volcanic fumaroles. It is highly hygroscopic and will rapidly deliquesce when exposed to ambient humidity, meaning it must be stored in a sealed, dry container to prevent dissolution.
Is this chlormanganokalite?
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 chlormanganokalite with a known reference. Chlormanganokalite sits at Mohs 2.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: light yellow.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: yellow, light yellow.
- 5Look at form & habitCrystal system: trigonal. Typical habit: tabular to rhombohedral crystals, often massive or as efflorescent crusts.
Often confused with
Chlormanganokalite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside chlormanganokalite
Minerals reported to co-occur with chlormanganokalite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- K₄MnCl₆
- Mohs hardness
- 2.5
- Density
- 2.31 g/cm³
- Colors
- Streak
- Light yellow
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Trigonal
- Crystal habit
- Tabular to rhombohedral crystals, often massive or as efflorescent crusts
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In cavities in ejected scoria
Where rockhounds find chlormanganokalite
Classic worldwide localities
- Vesuvius, Campania, Italy
Field-hunting tip
Where it forms: In cavities in ejected scoria. If you start seeing halite, sylvite, hematite in float, you are in the right ground. Typical habit: tabular to rhombohedral crystals, often massive or as efflorescent crusts. Train your eye for that shape before scanning the outcrop.



