Fangite is a rare thallium arsenic sulfosalt typically found as thin crusts or small yellow aggregates in hydrothermal deposits. It is a highly sought-after species for mineral collectors due to its rarity and association with other thallium-bearing minerals.
Is this fangite?
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 fangite with a known reference. Fangite 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. Fangite leaves a yellow streak.
- 3Read the lusterHold the specimen under a strong light. Fangite typically shows a adamantine luster.
- 4Match the color rangeCompare against the expected color range: yellow, orange-yellow.
- 5Look at form & habitCrystal system: tetragonal. Typical habit: microcrystalline aggregates, crusts, or radiating crystals.
Often confused with
Fangite vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside fangite
Minerals reported to co-occur with fangite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Tl₃AsS₄
- Mohs hardness
- 2
- Density
- 3.55 g/cm³
- Colors
- Streak
- Yellow
- Luster
- Adamantine
- Transparency
- Translucent
- Crystal system
- Tetragonal
- Crystal habit
- Microcrystalline Aggregates, Crusts, Or Radiating Crystals
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Hydrothermal Gold Deposits
- Typical price
- $100-500 per specimen
Where rockhounds find fangite
Classic worldwide localities
- Getchell mine, Nevada, USA
Field-hunting tip
Look in hydrothermal gold deposits country — that is the host setting where fangite typically forms. If you start seeing orpiment, realgar, lorandite in float, you are in the right ground. Field specimens usually show a microcrystalline aggregates, crusts, or radiating crystals habit, so train your eye for that shape before scanning the outcrop.




