Irarsite is a very rare platinum-group mineral typically found in heavy mineral concentrates of alluvial deposits or ultramafic complexes. It is a metallic mineral identified by its distinct silver-white color and high density, often requiring X-ray diffraction or microprobe analysis to distinguish it from other rare platinum-group species.
Is this irarsite?
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 irarsite with a known reference. Irarsite sits at Mohs 6, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Irarsite leaves a black streak.
- 3Read the lusterHold the specimen under a strong light. Irarsite typically shows a metallic luster.
- 4Match the color rangeCompare against the expected color range: silver-white, steel-gray.
- 5Look at form & habitCrystal system: cubic. Typical habit: small euhedral crystals, granular, massive.
Often confused with
Irarsite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Irarsite leaves black, Cobaltite leaves greyish-black.
How to tell apart: Streak differs, so Irarsite leaves black, Gersdorffite leaves grayish-black.
How to tell apart: Streak differs, so Irarsite leaves black, Hollingworthite leaves grayish-black.
Often found alongside irarsite
Minerals reported to co-occur with irarsite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- IrAsS
- Mohs hardness
- 6
- Density
- 9.5-9.8 g/cm³
- Colors
- Streak
- Black
- Luster
- Metallic
- Transparency
- Opaque
- Crystal system
- Cubic
- Crystal habit
- Small Euhedral Crystals, Granular, Massive
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Ultramafic Igneous Rocks and Placers
- Typical price
- $50-300 per small specimen
Where rockhounds find irarsite
Classic worldwide localities
- Yubdo, Ethiopia
- Witwatersrand, South Africa
- Kondyor Massif, Russia
- Sudbury, Canada
Field-hunting tip
Look in ultramafic igneous rocks and placers country, the host setting where irarsite typically forms. If you start seeing platinum, osmium, rutheniridosmine in float, you are in the right ground. Field specimens usually show a small euhedral crystals, granular, massive habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify irarsite?+
Where is irarsite found?+
How much is irarsite worth?+
Is irarsite safe to handle?+
What rocks look like irarsite?+
What minerals are found with irarsite?+
What kind of rock does irarsite form in?+
What is irarsite used for?+
Find irarsite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
