Dietzeite is a rare calcium iodate chromate mineral exclusively found in the hyper-arid nitrate deposits of the Atacama Desert. Collectors prize it for its vibrant yellow to orange-yellow color and distinct crystal habits, though it is highly sensitive to moisture and should be stored in a dry environment.
Is this dietzeite?
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 dietzeite with a known reference. Dietzeite sits at Mohs 3.5, 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: golden yellow.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: prismatic to acicular crystals, often as crusts or granular aggregates.
Often confused with
Dietzeite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside dietzeite
Minerals reported to co-occur with dietzeite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Ca₂(IO₃)₂CrO₄·H₂O
- Mohs hardness
- 3.5
- Density
- 3.62-3.70 g/cm³
- Colors
- Streak
- Light yellow
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Monoclinic
- Crystal habit
- Prismatic to acicular crystals, often as crusts or granular aggregates
- Cleavage
- On {100}, interrupted
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In nitrate deposits in an arid region
Where rockhounds find dietzeite
Classic worldwide localities
- Atacama Desert, Chile (type locality)
Field-hunting tip
Where it forms: In nitrate deposits in an arid region. If you start seeing lopezite, tarapacáite, ulexite in float, you are in the right ground. Typical habit: prismatic to acicular crystals, often as crusts or granular aggregates. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify dietzeite?+
Where is dietzeite found?+
Is dietzeite safe to handle?+
What rocks look like dietzeite?+
What minerals are found with dietzeite?+
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Find dietzeite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
