Kolwezite is a rare copper-cobalt carbonate mineral named after its type locality in the Kolwezi mining district. It is typically found as crusts or botryoidal masses in the oxidized zones of copper deposits, often showing a distinctive light to medium green color.

Hardness
3.5-4
Mohs
Luster
Pearly
Streak
Light Green
Transparency
Translucent

Is this kolwezite?

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 kolwezite with a known reference. Kolwezite sits at Mohs 3.5-4 — softer than the next harder reference, harder than the previous one.
  • 2
    Check the streak
    Drag the specimen across an unglazed porcelain plate. Kolwezite leaves a light green streak.
  • 3
    Read the luster
    Hold the specimen under a strong light. Kolwezite typically shows a pearly luster.
  • 4
    Match the color range
    Compare against the expected color range: green, brownish-green, pinkish.
  • 5
    Look at form & habit
    Crystal system: monoclinic. Typical habit: botryoidal, crusts, aggregates of lath-like crystals.

Often confused with

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

Often found alongside kolwezite

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

All properties

Chemical formula
(Cu,Co)₂(CO₃)(OH)₂
Mohs hardness
3.5-4
Density
3.85 g/cm³
Streak
Light Green
Luster
Pearly
Transparency
Translucent
Crystal system
Monoclinic
Crystal habit
Botryoidal, Crusts, Aggregates of Lath-like Crystals
Cleavage
Perfect On {010}
Rarity
Rare
Uses
Collector
Host rock
Oxidized Zones of Copper-cobalt Deposits
Typical price
$20-150 for thumbnail to small cabinet specimens

Where rockhounds find kolwezite

Classic worldwide localities

  • Kolwezi, Democratic Republic of the Congo
  • Kamoto, Democratic Republic of the Congo
  • Shaba Province, Democratic Republic of the Congo

Field-hunting tip

Look in oxidized zones of copper-cobalt deposits country — that is the host setting where kolwezite typically forms. If you start seeing malachite, heterogenite, chrysocolla in float, you are in the right ground. Field specimens usually show a botryoidal, crusts, aggregates of lath-like crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify kolwezite?+
Mohs hardness is 3.5-4. It typically shows a pearly luster. The streak is light green. Common colors include green, brownish-green, pinkish.
Where is kolwezite found?+
Notable localities include Kolwezi, Democratic Republic of the Congo; Kamoto, Democratic Republic of the Congo; Shaba Province, Democratic Republic of the Congo.
How much is kolwezite worth?+
Typical asking prices fall in the range of $20-150 for thumbnail to small cabinet specimens. Quality, size, and provenance can move individual specimens well outside that range.
Is kolwezite safe to handle?+
It contains toxic constituents. Contains copper and cobalt; should be handled with care. Avoid inhalation of dust and wash hands thoroughly after handling specimens. Handle with care, avoid grinding or breathing dust, and store separately.
What rocks look like kolwezite?+
Kolwezite is most often confused with Aurichalcite, Malachite, Hydrozincite. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with kolwezite?+
Kolwezite commonly co-occurs with Malachite, Heterogenite, Chrysocolla, Carrollite. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does kolwezite form in?+
Kolwezite typically forms in oxidized zones of copper-cobalt deposits. Working float back to the host body is the standard way to chase a fresh occurrence.
What is kolwezite used for?+
Kolwezite is used in collector.

Find kolwezite on the map

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