Trögerite is a rare secondary uranium arsenate mineral typically found as small, thin, transparent-to-translucent tabular crystals. It is most famous for its association with uranium deposits in the Schneeberg district, where it forms in the oxidation zones of hydrothermal veins.
Is this trögerite?
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 trögerite with a known reference. Trögerite sits at Mohs 2-3, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: yellow.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous, pearly on {001} cleavage.
- 4Match the color rangeCompare against the expected color range: yellow.
- 5Look at form & habitCrystal system: tetragonal. Typical habit: massive, striated.
Often confused with
Trögerite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Trögerite leaves yellow, Autunite leaves pale yellow.
How to tell apart: Streak differs, so Trögerite leaves yellow, Torbernite leaves pale green.
How to tell apart: Streak differs, so Trögerite leaves yellow, Uranocircite leaves light yellow; luster reads vitreous, pearly on {001} cleavage on Trögerite and pearly on Uranocircite.
Often found alongside trögerite
Minerals reported to co-occur with trögerite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (H₃O)(UO₂)(AsO₄)·3H₂O
- Mohs hardness
- 2-3
- Density
- 3.3 g/cm³
- Colors
- Streak
- Yellow
- Luster
- Vitreous, pearly on {001} cleavage
- Transparency
- Transparent
- Crystal system
- Tetragonal
- Crystal habit
- Massive, striated
- Cleavage
- On {001}, perfect; on {100}, good; on {011}, probable
- Fluorescence
- Lemon-yellow under SW and LW UV
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A rare mineral formed in the oxidation zone of some uranium deposits
Where rockhounds find trögerite
Classic worldwide localities
- Bald Mountain district, Lawrence Co., South Dakota, USA
- Walpurgis vein, in the Weisser Hirsch mine, and at the Daniel mine, Neustädtel-Schneeberg, Saxony, Germany
- Marbruie, near Dalbeattie, Kirkcudbrightshire, Scotland
- Rabéjac, Riviéral, and Mas-d’Alary uranium deposits, near Lodève, Hérault, France
- Bota-Burum uranium deposit, 15 km southwest of Alakol Lake, Chu-Ili Mountains, southwestern Balkhash district, Kazakhstan
Field-hunting tip
Where it forms: A rare mineral formed in the oxidation zone of some uranium deposits. If you start seeing walpurgite, uranospinite, uranospathite in float, you are in the right ground. Typical habit: massive, striated. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify trögerite?+
Where is trögerite found?+
Is trögerite safe to handle?+
What rocks look like trögerite?+
What minerals are found with trögerite?+
What kind of rock does trögerite form in?+
What is trögerite used for?+
Find trögerite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
