Aktashite is a rare copper-mercury-arsenic sulfosalt that typically occurs as metallic gray to black masses within hydrothermal veins. It is most frequently found in mercury-rich deposits alongside minerals like cinnabar and realgar. Due to its toxic composition, collectors should store specimens in sealed containers and avoid generating dust.

Hardness

3-3.5

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrare

Aktashite

Hardness: 3-3.5
Luster: Metallic
Streak: Black
Transparency: Opaque

Is this aktashite?

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 aktashite with a known reference. Aktashite sits at Mohs 3-3.5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Aktashite leaves a black streak.
3
Read the luster
Hold the specimen under a strong light. Aktashite typically shows a metallic luster.
4
Match the color range
Compare against the expected color range: gray, black.
5
Look at form & habit
Crystal system: trigonal. Typical habit: massive, granular.

Often confused with

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

Often found alongside aktashite

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

All properties

Chemical formula: Cu₆Hg₃As₄S₁₂
Mohs hardness: 3-3.5
Density: 5.68 g/cm³
Colors: Gray Black
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Trigonal
Crystal habit: Massive, Granular
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Hydrothermal Veins
Typical price: $50-300 per specimen depending on size and quality

Where rockhounds find aktashite

Classic worldwide localities

Aktash deposit, Altai Mountains, Russia
Khaidarkan, Kyrgyzstan

Field-hunting tip

Look in hydrothermal veins country — that is the host setting where aktashite typically forms. If you start seeing cinnabar, realgar, stibnite in float, you are in the right ground. Field specimens usually show a massive, granular habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify aktashite?+

Mohs hardness is 3-3.5. It typically shows a metallic luster. The streak is black. Common colors include gray, black.

Where is aktashite found?+

Notable localities include Aktash deposit, Altai Mountains, Russia; Khaidarkan, Kyrgyzstan.

How much is aktashite worth?+

Typical asking prices fall in the range of $50-300 per specimen depending on size and quality. Quality, size, and provenance can move individual specimens well outside that range.

Is aktashite safe to handle?+

It contains toxic constituents. Contains mercury and arsenic; handle with care and wash hands thoroughly after handling. Do not ingest dust or inhale particles. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like aktashite?+

Aktashite is most often confused with Tetrahedrite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with aktashite?+

Aktashite commonly co-occurs with Cinnabar, Realgar, Stibnite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does aktashite form in?+

Aktashite typically forms in hydrothermal veins. Working float back to the host body is the standard way to chase a fresh occurrence.

What is aktashite used for?+

Aktashite is used in collector.

Find aktashite on the map

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