Roquesite is a rare copper indium sulfide mineral that typically occurs as microscopic grains within other sulfide minerals like chalcopyrite. It is found in hydrothermal polymetallic deposits where indium enrichment has occurred, making it a significant mineral for geological study rather than large-scale aesthetic collection.
Is this roquesite?
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 roquesite with a known reference. Roquesite sits at Mohs 3.5-4, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: black.
- 3Read the lusterHold the specimen under a strong light. Luster: metallic.
- 4Match the color rangeCompare against the expected color range: gray.
- 5Look at form & habitCrystal system: tetragonal. Typical habit: inclusions.
Often confused with
Roquesite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Roquesite leaves black, Chalcopyrite leaves greenish black.
How to tell apart: Streak differs, so Roquesite leaves black, Sphalerite leaves pale brown to pale yellow and white; luster reads metallic on Roquesite and resinous to adamantine on Sphalerite.
How to tell apart: Streak differs, so Roquesite leaves black, Stannite leaves blackish.
Often found alongside roquesite
Minerals reported to co-occur with roquesite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- CuInS₂
- Mohs hardness
- 3.5-4
- Density
- 4.78 g/cm³
- Colors
- Streak
- Black
- Luster
- Metallic
- Transparency
- Opaque
- Crystal system
- Tetragonal
- Crystal habit
- Inclusions
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In association with copper sulfides in high-temperature Sn–W–Bi–Mo hydrothermal veins in highly metamorphosed rocks (Charrier, France); a late-stage mineral in a skarn Fe–W ore pipe (Ulsan mine, South Korea)
Where rockhounds find roquesite
Classic worldwide localities
- Sure Fire mine, Pyramid district, Washoe Co., Nevada, USA
- Charrier, Allier (type locality), France
- Lautaret Pass, Hautes-Alpes, France
- La Telhaie, Morbihan, France
- Vaultry, Haute-Vienne, France
- Geevor mine, St. Just, Cornwall, England
Field-hunting tip
Where it forms: In association with copper sulfides in high-temperature Sn–W–Bi–Mo hydrothermal veins in highly metamorphosed rocks (Charrier, France); a late-stage mineral in a skarn Fe–W ore pipe (Ulsan mine, South Korea). If you start seeing chalcopyrite, bornite, cubanite in float, you are in the right ground. Typical habit: inclusions. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify roquesite?+
Where is roquesite found?+
Is roquesite safe to handle?+
What rocks look like roquesite?+
What minerals are found with roquesite?+
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Find roquesite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
