Joëlbruggerite is a rare tellurate mineral typically found as delicate, needle-like crystals in oxidized ore deposits. It is best identified by its vibrant yellowish-green color and radial habit, often requiring magnification for accurate field identification.
Is this joëlbruggerite?
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 joëlbruggerite with a known reference. Joëlbruggerite sits at Mohs ~3, 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: adamantine.
- 4Match the color rangeCompare against the expected color range: bluish purple, grayish purple.
- 5Look at form & habitCrystal system: trigonal. Typical habit: acicular crystals, radiating sprays.
Often confused with
Joëlbruggerite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside joëlbruggerite
Minerals reported to co-occur with joëlbruggerite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Pb₃Zn₃SbAs₂O₁₃(OH)
- Mohs hardness
- ~3
- Density
- 6.73 g/cm³
- Colors
- Bluish purpleGrayish purple
- Streak
- White
- Luster
- Adamantine
- Transparency
- Transparent
- Crystal system
- Trigonal
- Crystal habit
- Acicular crystals, radiating sprays
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A secondary mineral from the oxidation of a silver-bearing tetrahedrite, hübnerite, and pyrite deposit
Where rockhounds find joëlbruggerite
Classic worldwide localities
- Black Pine mine, 14.5 km northwest of Philipsburg, Granite County, Montana, USA
Field-hunting tip
Where it forms: A secondary mineral from the oxidation of a silver-bearing tetrahedrite, hübnerite, and pyrite deposit. If you start seeing mimetite, malachite, azurite in float, you are in the right ground. Typical habit: acicular crystals, radiating sprays. Train your eye for that shape before scanning the outcrop.







