Naumannite is a rare silver selenide mineral typically found in low-temperature hydrothermal veins. It is distinguished by its heavy feel, metallic lead-gray color, and characteristic association with other rare selenides and precious metals.

Hardness
2.5
Mohs
Luster
Metallic
Streak
Black
Transparency
Opaque

Is this naumannite?

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 naumannite with a known reference. Naumannite sits at Mohs 2.5 — softer than the next harder reference, harder than the previous one.
  • 2
    Check the streak
    Drag the specimen across an unglazed porcelain plate. Naumannite leaves a black streak.
  • 3
    Read the luster
    Hold the specimen under a strong light. Naumannite typically shows a metallic luster.
  • 4
    Match the color range
    Compare against the expected color range: lead-gray, iron-black.
  • 5
    Look at form & habit
    Crystal system: orthorhombic. Typical habit: massive, granular, or rare tabular crystals.

Often confused with

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

Often found alongside naumannite

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

All properties

Chemical formula
Ag₂Se
Mohs hardness
2.5
Density
8.0-8.1 g/cm³
Streak
Black
Luster
Metallic
Transparency
Opaque
Crystal system
Orthorhombic
Crystal habit
Massive, Granular, Or Rare Tabular Crystals
Cleavage
None
Rarity
Rare
Uses
Collector, Ore of Silver
Host rock
Epithermal Hydrothermal Veins
Typical price
$20-200 depending on specimen size and purity

Where rockhounds find naumannite

Classic worldwide localities

  • Tilkerode, Germany
  • De Lamar, Idaho, USA
  • Guanajuato, Mexico
  • Tonopah, Nevada, USA
  • Kongsberg, Norway

Field-hunting tip

Look in epithermal hydrothermal veins country — that is the host setting where naumannite typically forms. If you start seeing acanthite, aguilarite, calcite in float, you are in the right ground. Field specimens usually show a massive, granular, or rare tabular crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify naumannite?+
Mohs hardness is 2.5. It typically shows a metallic luster. The streak is black. Common colors include lead-gray, iron-black.
Where is naumannite found?+
Notable localities include Tilkerode, Germany; De Lamar, Idaho, USA; Guanajuato, Mexico; Tonopah, Nevada, USA; Kongsberg, Norway.
How much is naumannite worth?+
Typical asking prices fall in the range of $20-200 depending on specimen size and purity. Quality, size, and provenance can move individual specimens well outside that range.
Is naumannite safe to handle?+
It contains toxic constituents. Contains silver and selenium; dust and fumes are toxic if inhaled or ingested. Wash hands thoroughly after handling and avoid creating dust when prepping specimens. Handle with care, avoid grinding or breathing dust, and store separately.
What rocks look like naumannite?+
Naumannite is most often confused with Argentite, Acanthite, Galena. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with naumannite?+
Naumannite commonly co-occurs with Acanthite, Aguilarite, Calcite, Quartz, Gold. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does naumannite form in?+
Naumannite typically forms in epithermal hydrothermal veins. Working float back to the host body is the standard way to chase a fresh occurrence.
What is naumannite used for?+
Naumannite is used in collector, ore of silver.

Find naumannite on the map

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