Cupromolybdite is a rare secondary mineral typically found in the oxidized zones of copper-molybdenum deposits. Collectors should look for vibrant green, tabular crystals or crusts often associated with other copper molybdates like lindgrenite.

Hardness
3-3.5
Mohs
Luster
Vitreous
Streak
Pale Green
Transparency
Translucent

Is this cupromolybdite?

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 cupromolybdite with a known reference. Cupromolybdite sits at Mohs 3-3.5 — softer than the next harder reference, harder than the previous one.
  • 2
    Check the streak
    Drag the specimen across an unglazed porcelain plate. Cupromolybdite leaves a pale green streak.
  • 3
    Read the luster
    Hold the specimen under a strong light. Cupromolybdite typically shows a vitreous luster.
  • 4
    Match the color range
    Compare against the expected color range: green, yellow-green.
  • 5
    Look at form & habit
    Crystal system: triclinic. Typical habit: tabular crystals, crusts, massive.

Often confused with

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

Often found alongside cupromolybdite

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

All properties

Chemical formula
Cu₃(MoO₄)₂
Mohs hardness
3-3.5
Density
4.41 g/cm³
Streak
Pale Green
Luster
Vitreous
Transparency
Translucent
Crystal system
Triclinic
Crystal habit
Tabular Crystals, Crusts, Massive
Cleavage
Distinct On {001}
Rarity
Rare
Uses
Collector
Host rock
Oxidized Zones of Copper-molybdenum Deposits
Typical price
$50-500 depending on specimen quality

Where rockhounds find cupromolybdite

Classic worldwide localities

  • Chuquicamata Mine, Chile
  • Bisbee, Arizona, USA
  • Tsumeb, Namibia

Field-hunting tip

Look in oxidized zones of copper-molybdenum deposits country — that is the host setting where cupromolybdite typically forms. If you start seeing lindgrenite, chrysocolla, molybdenite in float, you are in the right ground. Field specimens usually show a tabular crystals, crusts, massive habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify cupromolybdite?+
Mohs hardness is 3-3.5. It typically shows a vitreous luster. The streak is pale green. Common colors include green, yellow-green.
Where is cupromolybdite found?+
Notable localities include Chuquicamata Mine, Chile; Bisbee, Arizona, USA; Tsumeb, Namibia.
How much is cupromolybdite worth?+
Typical asking prices fall in the range of $50-500 depending on specimen quality. Quality, size, and provenance can move individual specimens well outside that range.
What rocks look like cupromolybdite?+
Cupromolybdite is most often confused with Lindgrenite, Euchroite, Atacamite. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with cupromolybdite?+
Cupromolybdite commonly co-occurs with Lindgrenite, Chrysocolla, Molybdenite, Azurite. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does cupromolybdite form in?+
Cupromolybdite typically forms in oxidized zones of copper-molybdenum deposits. Working float back to the host body is the standard way to chase a fresh occurrence.
What is cupromolybdite used for?+
Cupromolybdite is used in collector.

Find cupromolybdite on the map

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