Kainotropite is an extremely rare copper sulfate mineral found as a secondary mineral in oxidized ore deposits. It typically forms small, dark green tabular crystals that are difficult to distinguish from associated copper minerals without rigorous chemical testing or X-ray diffraction.

Hardness

Mohs

Luster

Vitreous

Streak

Light Green

Transparency

Translucent

mineralrare

Kainotropite

Hardness: 4
Luster: Vitreous
Streak: Light Green
Transparency: Translucent

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Is this kainotropite?

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 kainotropite with a known reference. Kainotropite 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. Kainotropite leaves a light green streak.
3
Read the luster
Hold the specimen under a strong light. Kainotropite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: dark green, black, olive green.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: tabular crystals, crusts.

Often confused with

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

How to tell apart: Streak differs, so Kainotropite leaves light green, Brochantite leaves pale-green.

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Often found alongside kainotropite

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

All properties

Chemical formula: Cu₄(SO₄)(OH)₆
Mohs hardness: 4
Density: 4.15 g/cm³
Colors: Dark Green Black Olive Green
Streak: Light Green
Luster: Vitreous
Transparency: Translucent
Crystal system: Orthorhombic
Crystal habit: Tabular Crystals, Crusts
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Oxidized Zones of Copper Deposits
Typical price: $50-300 per specimen

Where rockhounds find kainotropite

Classic worldwide localities

Chuquicamata Mine (Chile)

Field-hunting tip

Look in oxidized zones of copper deposits country, the host setting where kainotropite typically forms. If you start seeing antlerite, brochantite, chalcanthite in float, you are in the right ground. Field specimens usually show a tabular crystals, crusts habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify kainotropite?+

Mohs hardness is 4. It typically shows a vitreous luster. The streak is light green. Common colors include dark green, black, olive green.

Where is kainotropite found?+

Notable localities include Chuquicamata Mine (Chile).

How much is kainotropite worth?+

Typical asking prices fall in the range of $50-300 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

Is kainotropite safe to handle?+

It contains toxic constituents. Contains copper which is toxic if ingested or inhaled as dust; wash hands thoroughly after handling. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like kainotropite?+

Kainotropite is most often confused with Antlerite, Brochantite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with kainotropite?+

Kainotropite commonly co-occurs with Antlerite, Brochantite, Chalcanthite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does kainotropite form in?+

Kainotropite typically forms in oxidized zones of copper deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is kainotropite used for?+

Kainotropite is used in collector.

Find kainotropite on the map

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