Cuprorhodsite is a rare platinum-group mineral typically occurring as microscopic grains within massive sulfide deposits. It is most commonly identified in polished sections via reflected light microscopy or microprobe analysis due to its extreme scarcity in macroscopic sizes.

Hardness

5-5.5

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrareSpinel Group family

Cuprorhodsite

Hardness: 5-5.5
Luster: Metallic
Streak: Black
Transparency: Opaque

Is this cuprorhodsite?

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 cuprorhodsite with a known reference. Cuprorhodsite sits at Mohs 5-5.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Streak: black.
3
Read the luster
Hold the specimen under a strong light. Luster: metallic.
4
Match the color range
Compare against the expected color range: iron black, black.
5
Look at form & habit
Crystal system: cubic. Typical habit: microscopic grains, anhedral grains.

Often confused with

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

How to tell apart: Cuprorhodsite is noticeably harder (Mohs 5-5.5 vs. 1.5); streak differs, so Cuprorhodsite leaves black, Braggite leaves gray.

How to tell apart: Laurite is the harder of the two (Mohs 7.5 vs. 5-5.5); streak differs, so Cuprorhodsite leaves black, Laurite leaves dark gray.

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Often found alongside cuprorhodsite

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

All properties

Chemical formula: (Cu₀.₅Fe₀.₅)Rh₂S₄
Mohs hardness: 5-5.5
Density: 6.74 g/cm³
Colors: Iron black Black
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Cubic
Crystal habit: Microscopic grains, anhedral grains
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: In alluvial placers

Where rockhounds find cuprorhodsite

Classic worldwide localities

Gusevogorskii massif, Ural Mountains (type locality), and in the Far Eastern Region, from the Chad massif, Khabarovsk Territory, on Mt. Filipp, Kamchatka, and in the Baimka placers, Chukota, Russia
Chromwerk, Kraubath massif, Styria, Austria

Field-hunting tip

Where it forms: In alluvial placers. If you start seeing isoferroplatinum, cuproiridsite, malanite in float, you are in the right ground. Typical habit: microscopic grains, anhedral grains. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify cuprorhodsite?+

Mohs hardness is 5-5.5. Luster: metallic. The streak is black. Common colors include iron black, black.

Where is cuprorhodsite found?+

Notable localities include Gusevogorskii massif, Ural Mountains (type locality), and in the Far Eastern Region, from the Chad massif, Khabarovsk Territory, on Mt. Filipp, Kamchatka, and in the Baimka placers, Chukota, Russia; Chromwerk, Kraubath massif, Styria, Austria.

Is cuprorhodsite safe to handle?+

Cuprorhodsite contains copper. Wash your hands afterwards, never grind or breathe the dust, and store it apart from specimens you handle often.

What rocks look like cuprorhodsite?+

Cuprorhodsite is most often confused with Cooperite, Braggite, Laurite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with cuprorhodsite?+

Cuprorhodsite commonly co-occurs with Isoferroplatinum, Cuproiridsite, Malanite, Osmium, Iridosmine, Laurite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does cuprorhodsite form in?+

Where it forms: In alluvial placers. Working float back to the host body is the standard way to chase a fresh occurrence.

What is cuprorhodsite used for?+

Cuprorhodsite is used in collector.

Find cuprorhodsite on the map

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