Goldfieldite is a rare tellurium-rich member of the tetrahedrite group, typically appearing as metallic, steel-gray to black tetrahedral crystals or massive aggregates. It is primarily found in epithermal gold-telluride deposits, often associated with other rare tellurium-bearing minerals and quartz.

Hardness

3-3.5

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrareTetrahedrite Group family

Goldfieldite

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

Is this goldfieldite?

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 goldfieldite with a known reference. Goldfieldite 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. Goldfieldite leaves a black streak.
3
Read the luster
Hold the specimen under a strong light. Goldfieldite typically shows a metallic luster.
4
Match the color range
Compare against the expected color range: steel-gray, iron-black.
5
Look at form & habit
Crystal system: cubic. Typical habit: tetrahedral crystals, massive, granular.

Often confused with

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

How to tell apart: Streak differs, so Goldfieldite leaves black, Enargite leaves grayish-black.

Compare →

Often found alongside goldfieldite

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

All properties

Chemical formula: Cu₁₂Te₄S₁₃
Mohs hardness: 3-3.5
Density: 5.3-5.5 g/cm³
Colors: Steel-gray Iron-black
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Cubic
Crystal habit: Tetrahedral Crystals, Massive, Granular
Cleavage: None
Rarity: Rare
Uses: Collector, Scientific Study
Host rock: Hydrothermal Veins
Typical price: $20-200 depending on specimen size and matrix quality

Where rockhounds find goldfieldite

Classic worldwide localities

Goldfield, Nevada, USA
Kawazu mine, Japan
Moctezuma, Mexico
Bajan, Romania

Field-hunting tip

Look in hydrothermal veins country, the host setting where goldfieldite typically forms. If you start seeing tellurides, pyrite, quartz in float, you are in the right ground. Field specimens usually show a tetrahedral crystals, massive, granular habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify goldfieldite?+

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

Where is goldfieldite found?+

Notable localities include Goldfield, Nevada, USA; Kawazu mine, Japan; Moctezuma, Mexico; Bajan, Romania.

How much is goldfieldite worth?+

Typical asking prices fall in the range of $20-200 depending on specimen size and matrix quality. Quality, size, and provenance can move individual specimens well outside that range.

Is goldfieldite safe to handle?+

It contains toxic constituents. Contains tellurium and copper; dust should not be inhaled and hands should be washed after handling as it can release toxic fumes if heated. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like goldfieldite?+

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

What minerals are found with goldfieldite?+

Goldfieldite commonly co-occurs with Tellurides, Pyrite, Quartz, Enargite, Barite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does goldfieldite form in?+

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

What is goldfieldite used for?+

Goldfieldite is used in collector, scientific study.

Find goldfieldite on the map

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