Dietrichite is a rare zinc-dominant sulfate mineral that typically forms as delicate, white, fibrous crusts or tufts in the oxidized zones of sulfide mines. Because it is highly soluble and easily dehydrated, collectors must store these specimens in a dry, sealed environment to prevent them from breaking down or losing their crystal habit.
Is this dietrichite?
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 dietrichite with a known reference. Dietrichite 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. Dietrichite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Dietrichite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: white, colorless, yellowish.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: fibrous to acicular crusts and efflorescences.
Often confused with
Dietrichite vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside dietrichite
Minerals reported to co-occur with dietrichite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (Zn,Fe²⁺,Mn²⁺)Al₂(SO₄)₄·22H₂O
- Mohs hardness
- 2
- Density
- 1.81 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Fibrous to Acicular Crusts and Efflorescences
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Oxidized Zones of Sulfide Ore Deposits
- Typical price
- $20-100 for small specimen
Where rockhounds find dietrichite
Classic worldwide localities
- Karlovy Vary, Czech Republic
- Aznalcóllar, Spain
- Rio Marina, Italy
Field-hunting tip
Look in oxidized zones of sulfide ore deposits country — that is the host setting where dietrichite typically forms. If you start seeing pyrite, gypsum, melanterite in float, you are in the right ground. Field specimens usually show a fibrous to acicular crusts and efflorescences habit, so train your eye for that shape before scanning the outcrop.






