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.

Hardness

Mohs

Luster

Adamantine

Streak

Yellow

Transparency

Translucent

mineralrare

Fangite

Hardness: 2
Luster: Adamantine
Streak: Yellow
Transparency: Translucent

Is this fangite?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

1
Test the hardness
Try to scratch fangite with a known reference. Fangite sits at Mohs 2, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Fangite leaves a yellow streak.
3
Read the luster
Hold the specimen under a strong light. Fangite typically shows a adamantine luster.
4
Match the color range
Compare against the expected color range: yellow, orange-yellow.
5
Look at form & habit
Crystal 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.

mineral

Orpiment

Mohs 1.5-2

How to tell apart: Luster reads adamantine on Fangite and resinous on Orpiment.

How to tell apart: Streak differs, so Fangite leaves yellow, Realgar leaves orange-red; luster reads adamantine on Fangite and resinous on Realgar.

Compare →

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: Yellow Orange-yellow
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, 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.

Common questions

How do you identify fangite?+

Mohs hardness is 2. It typically shows a adamantine luster. The streak is yellow. Common colors include yellow, orange-yellow.

Where is fangite found?+

Notable localities include Getchell mine, Nevada, USA.

How much is fangite worth?+

Typical asking prices fall in the range of $100-500 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

Is fangite safe to handle?+

It contains toxic constituents. Contains thallium and arsenic; avoid skin contact, ingestion, or inhalation of dust. Always wash hands thoroughly after handling. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like fangite?+

Fangite is most often confused with Orpiment, Realgar. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with fangite?+

Fangite commonly co-occurs with Orpiment, Realgar, Lorandite, Pyrite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does fangite form in?+

Fangite typically forms in hydrothermal gold deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is fangite used for?+

Fangite is used in collector.

Find fangite on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.