Despujolsite is a very rare hydrated calcium strontium sulfate mineral primarily known from fumarolic environments. It typically forms clear, prismatic, hexagonal crystals that are often associated with other sulfate minerals like ettringite. Because of its scarcity, it is sought after primarily by advanced mineral collectors specializing in rare sulfates.
Is this despujolsite?
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 despujolsite with a known reference. Despujolsite 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: white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: lemon.
- 5Look at form & habitCrystal system: hexagonal. Typical habit: prismatic crystals.
Often confused with
Despujolsite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside despujolsite
Minerals reported to co-occur with despujolsite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Ca₃Mn(SO₄)₂(OH)₆·3H₂O
- Mohs hardness
- 2.5
- Density
- 2.46 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent to translucent
- Crystal system
- Hexagonal
- Crystal habit
- Prismatic crystals
- Cleavage
- Good
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In a hydrothermal manganese deposit
Where rockhounds find despujolsite
Classic worldwide localities
- Tachgagalt, 17 km south of Ouarzazate, Anti-Atlas Mountains, Morocco
Field-hunting tip
Where it forms: In a hydrothermal manganese deposit. If you start seeing gaudefroyite in float, you are in the right ground. Typical habit: prismatic crystals. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify despujolsite?+
Where is despujolsite found?+
What rocks look like despujolsite?+
What minerals are found with despujolsite?+
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What is despujolsite used for?+
Find despujolsite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
