Vaughanite is an extremely rare thallium-mercury sulfosalt primarily found in gold-bearing hydrothermal deposits. Collectors usually encounter it as microscopic grains embedded within ore samples, as large crystals are virtually unknown.

Hardness

2-3

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrare

Vaughanite

Hardness: 2-3
Luster: Metallic
Streak: Black
Transparency: Opaque

Is this vaughanite?

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 vaughanite with a known reference. Vaughanite sits at Mohs 2-3 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Vaughanite leaves a black streak.
3
Read the luster
Hold the specimen under a strong light. Vaughanite typically shows a metallic luster.
4
Match the color range
Compare against the expected color range: white, gray.
5
Look at form & habit
Crystal system: trigonal. Typical habit: grains, small masses.

Often confused with

Vaughanite vs. its common look-alikes — and how to tell them apart in the field.

mineral

Chalcostibite

Mohs 3-4

How to tell apart: Streak differs — Vaughanite leaves black, Chalcostibite leaves lead-gray.

How to tell apart: Streak differs — Vaughanite leaves black, Livingstonite leaves red.

Compare →

Often found alongside vaughanite

Minerals reported to co-occur with vaughanite. Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula: TlHgSb₄S₇
Mohs hardness: 2-3
Density: 7.5-7.7 g/cm³
Colors: White Gray
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Trigonal
Crystal habit: Grains, Small Masses
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Hydrothermal Gold Deposits
Typical price: $100-500 per specimen depending on size and rarity

Where rockhounds find vaughanite

Classic worldwide localities

Hemlo mine, Ontario, Canada

Field-hunting tip

Look in hydrothermal gold deposits country — that is the host setting where vaughanite typically forms. If you start seeing realgar, cinnabar, pyrite in float, you are in the right ground. Field specimens usually show a grains, small masses habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify vaughanite?+

Mohs hardness is 2-3. It typically shows a metallic luster. The streak is black. Common colors include white, gray.

Where is vaughanite found?+

Notable localities include Hemlo mine, Ontario, Canada.

How much is vaughanite worth?+

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

Is vaughanite safe to handle?+

It contains toxic constituents. Contains thallium, mercury, and arsenic; handle with extreme caution, wash hands thoroughly after handling, and avoid creating dust. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like vaughanite?+

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

What minerals are found with vaughanite?+

Vaughanite commonly co-occurs with realgar, cinnabar, pyrite, stibnite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does vaughanite form in?+

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

What is vaughanite used for?+

Vaughanite is used in collector.

Find vaughanite on the map

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