Calaverite is a rare gold telluride that typically occurs in low-temperature hydrothermal veins. It is distinguished by its yellowish-green streak and heavy weight, often forming complex, striated prismatic crystals that can be difficult to distinguish from krennerite without X-ray diffraction.
Is this calaverite?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch calaverite with a known reference. Calaverite sits at Mohs 2.5-3, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: greenish to yellowish gray.
- 3Read the lusterHold the specimen under a strong light. Luster: metallic.
- 4Match the color rangeCompare against the expected color range: yellow, yellowish white.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: crystalline, massive, striated.
Often confused with
Calaverite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Pyrite is the harder of the two (Mohs 6-6.5 vs. 2.5-3).
How to tell apart: Streak differs, so Calaverite leaves greenish to yellowish gray, Sylvanite leaves steel-gray to silver-white.
How to tell apart: Luster reads metallic on Calaverite and very high metallic on Krennerite.
Often found alongside calaverite
Minerals reported to co-occur with calaverite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- AuTe₂
- Mohs hardness
- 2.5-3
- Density
- 9.10-9.40 g/cm³
- Colors
- Streak
- Greenish to yellowish gray
- Luster
- Metallic
- Transparency
- Opaque
- Crystal system
- Monoclinic
- Crystal habit
- Crystalline, massive, striated
- Cleavage
- None
- Rarity
- Uncommon
- Uses
- Collector
- Host rock
- Typically in veins in low-temperature hydrothermal deposits, but also in medium-and high-temperature deposits
Where rockhounds find calaverite
1 mapped spotsClassic worldwide localities
- Stanislaus (type locality), Morgan, and Melones mines, Carson Hill district, Calaveras Co., California, USA
- Spotted Horse mine, Maiden, Fergus Co., and the Mayflower mine, Tobacco Root Mountains, Madison Co., Montana, USA
- Cripple Creek district, Teller Co., Colorado, USA
- Central City district, Gilpin Co., Colorado, USA
- San Francisco mine, 145 km north of Hermosillo, Sonora, Mexico
- El Indio mine, east of La Serena, Coquimbo, Chile
Field-hunting tip
Where it forms: Typically in veins in low-temperature hydrothermal deposits, but also in medium-and high-temperature deposits. If you start seeing altaite, coloradoite, krennerite in float, you are in the right ground. Typical habit: crystalline, massive, striated. Train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in Wisconsin. Start trip planning there.
Common questions
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Find calaverite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
