Hydrotungstite is a rare secondary tungsten mineral that typically forms as a result of the alteration of scheelite or other tungsten minerals. It is most commonly identified by its soft, yellow-to-green platy crystals that resemble mica, often found as crusts in weathered hydrothermal veins.
Is this hydrotungstite?
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 hydrotungstite with a known reference. Hydrotungstite 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. Hydrotungstite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Hydrotungstite typically shows a pearly luster.
- 4Match the color rangeCompare against the expected color range: yellow, yellowish-green, green.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: platy or micaceous aggregates, crusts.
Often confused with
Hydrotungstite vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside hydrotungstite
Minerals reported to co-occur with hydrotungstite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- WO₃·2H₂O
- Mohs hardness
- 2
- Density
- 4.6 g/cm³
- Streak
- White
- Luster
- Pearly
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Platy or Micaceous Aggregates, Crusts
- Cleavage
- Perfect
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Oxidized Tungsten Deposits
- Typical price
- $20-150 thumbnail
Where rockhounds find hydrotungstite
Classic worldwide localities
- Calacalani, Bolivia
- Oruro, Bolivia
- Bishop, California, USA
Field-hunting tip
Look in oxidized tungsten deposits country — that is the host setting where hydrotungstite typically forms. If you start seeing tungstite, scheelite, quartz in float, you are in the right ground. Field specimens usually show a platy or micaceous aggregates, crusts habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify hydrotungstite?+
Where is hydrotungstite found?+
How much is hydrotungstite worth?+
What rocks look like hydrotungstite?+
What minerals are found with hydrotungstite?+
What kind of rock does hydrotungstite form in?+
What is hydrotungstite used for?+
Find hydrotungstite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
