Tarkianite is an extremely rare copper-rhenium sulfide mineral found in hydrothermal ore deposits. It typically occurs as microscopic anhedral inclusions within other sulfide minerals, making it a difficult target for field collectors and usually requiring electron microprobe analysis for positive identification.

Hardness

3.5

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrare

Tarkianite

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

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Is this tarkianite?

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 tarkianite with a known reference. Tarkianite sits at Mohs 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. Tarkianite leaves a black streak.
3
Read the luster
Hold the specimen under a strong light. Tarkianite typically shows a metallic luster.
4
Match the color range
Compare against the expected color range: steel-gray, white.
5
Look at form & habit
Crystal system: cubic. Typical habit: anhedral to subhedral grains.

Often confused with

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

How to tell apart: Streak differs — Tarkianite leaves black, Bornite leaves greyish black.

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Often found alongside tarkianite

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

All properties

Chemical formula: (Cu,Fe)₃(Re,Mo)₄S₈
Mohs hardness: 3.5
Density: 9.4-9.5 g/cm³
Colors: Steel-gray White
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Cubic
Crystal habit: Anhedral to Subhedral Grains
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Hydrothermal Copper-molybdenum Deposits
Typical price: $100-500 per specimen

Where rockhounds find tarkianite

Classic worldwide localities

Kadzharan copper-molybdenum deposit, Armenia

Field-hunting tip

Look in hydrothermal copper-molybdenum deposits country — that is the host setting where tarkianite typically forms. If you start seeing chalcopyrite, molybdenite, galena in float, you are in the right ground. Field specimens usually show a anhedral to subhedral grains habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify tarkianite?+

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

Where is tarkianite found?+

Notable localities include Kadzharan copper-molybdenum deposit, Armenia.

How much is tarkianite 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 tarkianite safe to handle?+

It contains toxic constituents. Contains copper and potentially other heavy metals; avoid dust inhalation and wash hands thoroughly after handling. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like tarkianite?+

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

What minerals are found with tarkianite?+

Tarkianite commonly co-occurs with Chalcopyrite, Molybdenite, Galena. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does tarkianite form in?+

Tarkianite typically forms in hydrothermal copper-molybdenum deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is tarkianite used for?+

Tarkianite is used in collector.

Find tarkianite on the map

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