Antlerite is a secondary copper sulfate mineral often found as emerald-green acicular crystals or massive crusts in the oxidized zones of copper deposits. It is frequently confused with the closely related mineral brochantite, though it is usually distinguished by its specific crystal habit and chemical testing.
Is this antlerite?
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 antlerite with a known reference. Antlerite sits at Mohs 3.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: pale green.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: emerald green, green, light green, black, black green.
- 5Look at form & habitCrystal system: orthorhombic. Typical habit: acicular, concretionary, reniform.
Often confused with
Antlerite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Luster reads vitreous on Antlerite and adamantine to vitreous; silky if fibrous; dull to earthy if massive on Malachite.
How to tell apart: Streak differs, so Antlerite leaves pale green, Atacamite leaves apple-green; luster reads vitreous on Antlerite and adamantine to vitreous on Atacamite.
Often found alongside antlerite
Minerals reported to co-occur with antlerite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Cu₃SO₄(OH)₄
- Mohs hardness
- 3.5
- Density
- 3.88 g/cm³
- Streak
- Pale green
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Orthorhombic
- Crystal habit
- Acicular, concretionary, reniform
- Cleavage
- {010}, perfect; {100}, poor
- Rarity
- Uncommon
- Uses
- Collector, Specimen
- Host rock
- Uncommon, typically formed in the oxidized zone of copper deposits under highly acid conditions, especially in arid regions
Where rockhounds find antlerite
1 mapped spotsClassic worldwide localities
- Antler mine, near Yucca Station, Mohave Co., several mines in Bisbee, Cochise Co., from the Grandview mine, Grand Canyon, Coconino Co., in Copper Basin, between Skull Valley and Prescott, and at Jerome, Yavapai Co., Arizona, USA
- Blanchard mine, near Bingham, Hansonburg district, Socorro Co., New Mexico, USA
- Darwin district, Inyo Co., California, USA
- Northern Light mine, near Black Mountain, Mountain View district, Mineral Co., Nevada, USA
- Puerto de Gomez, Chihuahua, Mexico
- Chuquicamata, Antofagasta, and from Remolinos, Atacama, Chile
Field-hunting tip
Where it forms: Uncommon, typically formed in the oxidized zone of copper deposits under highly acid conditions, especially in arid regions. If you start seeing brochantite, atacamite, chalcanthite in float, you are in the right ground. Typical habit: acicular, concretionary, reniform. Train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in Utah. Start trip planning there.
Common questions
How do you identify antlerite?+
Where is antlerite found?+
Can I find antlerite in the United States?+
Is antlerite safe to handle?+
What rocks look like antlerite?+
What minerals are found with antlerite?+
What kind of rock does antlerite form in?+
What is antlerite used for?+
Find antlerite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
