Orthocuproplatinum is a very rare platinum-copper alloy typically found as minute inclusions within other platinum-group minerals. It is primarily identified through specialized analytical methods like electron microprobe analysis, appearing as small silver-white grains in reflected light under a microscope.

Hardness
4
Mohs
Luster
Metallic
Streak
Metallic White
Transparency
Opaque

Is this orthocuproplatinum?

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 orthocuproplatinum with a known reference. Orthocuproplatinum sits at Mohs 4 — softer than the next harder reference, harder than the previous one.
  • 2
    Check the streak
    Drag the specimen across an unglazed porcelain plate. Orthocuproplatinum leaves a metallic white streak.
  • 3
    Read the luster
    Hold the specimen under a strong light. Orthocuproplatinum typically shows a metallic luster.
  • 4
    Match the color range
    Compare against the expected color range: white, silver-white.
  • 5
    Look at form & habit
    Crystal system: orthorhombic. Typical habit: anhedral grains, inclusions in platinum group minerals.

Often confused with

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

Often found alongside orthocuproplatinum

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

All properties

Chemical formula
CuPt
Mohs hardness
4
Density
18.35 g/cm³
Streak
Metallic White
Luster
Metallic
Transparency
Opaque
Crystal system
Orthorhombic
Crystal habit
Anhedral Grains, Inclusions in Platinum Group Minerals
Cleavage
None
Rarity
Rare
Uses
Collector, Scientific Research
Host rock
Ultramafic Igneous Rocks
Typical price
$100-500 for micro-mounts

Where rockhounds find orthocuproplatinum

Classic worldwide localities

  • Ioko-Dovyren massif, Russia
  • Stillwater complex, USA
  • Bushveld complex, South Africa

Field-hunting tip

Look in ultramafic igneous rocks country — that is the host setting where orthocuproplatinum typically forms. If you start seeing platinum, cooperite, sperrylite in float, you are in the right ground. Field specimens usually show a anhedral grains, inclusions in platinum group minerals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify orthocuproplatinum?+
Mohs hardness is 4. It typically shows a metallic luster. The streak is metallic white. Common colors include white, silver-white.
Where is orthocuproplatinum found?+
Notable localities include Ioko-Dovyren massif, Russia; Stillwater complex, USA; Bushveld complex, South Africa.
How much is orthocuproplatinum worth?+
Typical asking prices fall in the range of $100-500 for micro-mounts. Quality, size, and provenance can move individual specimens well outside that range.
What rocks look like orthocuproplatinum?+
Orthocuproplatinum is most often confused with Isoferroplatinum, Tulameenite. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with orthocuproplatinum?+
Orthocuproplatinum commonly co-occurs with Platinum, Cooperite, Sperrylite, Chalcopyrite. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does orthocuproplatinum form in?+
Orthocuproplatinum typically forms in ultramafic igneous rocks. Working float back to the host body is the standard way to chase a fresh occurrence.
What is orthocuproplatinum used for?+
Orthocuproplatinum is used in collector, scientific research.

Find orthocuproplatinum on the map

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