Cherepanovite is an extremely rare rhodium arsenide typically found as microscopic inclusions within platinum-group mineral assemblages. It is usually identified through reflected light microscopy or electron microprobe analysis, appearing as small, pinkish-white metallic grains in ultramafic complexes.

Hardness
6
Mohs
Luster
Metallic
Streak
Grayish black
Transparency
Opaque

Is this cherepanovite?

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 cherepanovite with a known reference. Cherepanovite sits at Mohs 6, softer than the next harder reference, harder than the previous one.
  • 2
    Check the streak
    Drag the specimen across an unglazed porcelain plate. Streak: grayish 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: grayish black, black.
  • 5
    Look at form & habit
    Crystal system: orthorhombic. Typical habit: anhedral grains, disseminated inclusions.

Often confused with

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

Often found alongside cherepanovite

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

All properties

Chemical formula
RhAs
Mohs hardness
6
Density
9.72 g/cm³
Streak
Grayish black
Luster
Metallic
Transparency
Opaque
Crystal system
Orthorhombic
Crystal habit
Anhedral grains, disseminated inclusions
Cleavage
One distinct
Rarity
Rare
Uses
Collector
Host rock
In a placer with other platinum group element minerals derived from an ultramafic massif in an ophiolite belt (Northern Pekul’nei River, Russia)

Where rockhounds find cherepanovite

Classic worldwide localities

  • A placer of the Northern Pekul’nei River, Pekul’nei Range, eastern Chukot Peninsula (type locality), Russia
  • A placer in the Upper Miask River, Ural Mountains, Russia
  • Ray-Iz ophiolite complex, Polar Ural Mountains, Russia
  • Onverwacht pipe, in the Merensky Reef, Bushveld complex, Transvaal, South Africa

Field-hunting tip

Where it forms: In a placer with other platinum group element minerals derived from an ultramafic massif in an ophiolite belt (Northern Pekul’nei River, Russia). If you start seeing isoferroplatinum, tetraferroplatinum, ferronickelplatinum in float, you are in the right ground. Typical habit: anhedral grains, disseminated inclusions. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify cherepanovite?+
Mohs hardness is 6. Luster: metallic. The streak is grayish black. Common colors include grayish black, black.
Where is cherepanovite found?+
Notable localities include A placer of the Northern Pekul’nei River, Pekul’nei Range, eastern Chukot Peninsula (type locality), Russia; A placer in the Upper Miask River, Ural Mountains, Russia; Ray-Iz ophiolite complex, Polar Ural Mountains, Russia; Onverwacht pipe, in the Merensky Reef, Bushveld complex, Transvaal, South Africa.
Is cherepanovite safe to handle?+
Cherepanovite contains arsenic and calls for real care. Contains arsenic, which is toxic; handle with care and wash hands thoroughly after contact.
What rocks look like cherepanovite?+
Cherepanovite is most often confused with Sperrylite, Cooperite. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with cherepanovite?+
Cherepanovite commonly co-occurs with Isoferroplatinum, Tetraferroplatinum, Ferronickelplatinum, Rutheniridosmine, Laurite, Irarsite. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does cherepanovite form in?+
Where it forms: In a placer with other platinum group element minerals derived from an ultramafic massif in an ophiolite belt (Northern Pekul’nei River, Russia). Working float back to the host body is the standard way to chase a fresh occurrence.
What is cherepanovite used for?+
Cherepanovite is used in collector.

Find cherepanovite on the map

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