Umangite is a rare copper selenide mineral typically found as massive, granular aggregates with a striking violet-blue to dark blue color. It is almost exclusively identified by its metallic luster and association with other rare selenium-bearing minerals in hydrothermal vein deposits.

Hardness

2.5-3

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrare

Umangite

Hardness: 2.5-3
Luster: Metallic
Streak: Black
Transparency: Opaque

Is this umangite?

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 umangite with a known reference. Umangite sits at Mohs 2.5-3, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Umangite leaves a black streak.
3
Read the luster
Hold the specimen under a strong light. Umangite typically shows a metallic luster.
4
Match the color range
Compare against the expected color range: dark blue, violet-blue, reddish-violet.
5
Look at form & habit
Crystal system: tetragonal. Typical habit: massive, granular.

Often confused with

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

How to tell apart: Streak differs, so Umangite leaves black, Chalcopyrite leaves greenish-black.

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Often found alongside umangite

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

All properties

Chemical formula: Cu₃Se₂
Mohs hardness: 2.5-3
Density: 6.5-6.6 g/cm³
Colors: Dark Blue Violet-blue Reddish-violet
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Tetragonal
Crystal habit: Massive, Granular
Cleavage: None
Rarity: Rare
Uses: Collector, Ore of Copper
Host rock: Hydrothermal Veins
Typical price: $20-150 per specimen depending on size and rarity

Where rockhounds find umangite

Classic worldwide localities

Umango Mine, Argentina
Skrikerum, Sweden
Tlumacov, Czech Republic
Sierra de Umango, Argentina

Field-hunting tip

Look in hydrothermal veins country, the host setting where umangite typically forms. If you start seeing berzelianite, clausthalite, tiemannite 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 umangite?+

Mohs hardness is 2.5-3. It typically shows a metallic luster. The streak is black. Common colors include dark blue, violet-blue, reddish-violet.

Where is umangite found?+

Notable localities include Umango Mine, Argentina; Skrikerum, Sweden; Tlumacov, Czech Republic; Sierra de Umango, Argentina.

How much is umangite worth?+

Typical asking prices fall in the range of $20-150 per specimen depending on size and rarity. Quality, size, and provenance can move individual specimens well outside that range.

Is umangite safe to handle?+

It contains toxic constituents. Contains selenium, which is toxic if ingested or inhaled as dust. Handle with care and wash hands thoroughly after handling. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like umangite?+

Umangite is most often confused with Berzelianite, Klockmannite, Chalcopyrite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with umangite?+

Umangite commonly co-occurs with Berzelianite, Clausthalite, Tiemannite, Calcite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does umangite form in?+

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

What is umangite used for?+

Umangite is used in collector, ore of copper.

Find umangite on the map

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