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, so Vaughanite leaves black, Chalcostibite leaves lead-gray.

How to tell apart: Streak differs, so 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, 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.