Kimberlite is a rare, potassic volcanic rock best known as the primary host rock for diamonds. It typically occurs in vertical, carrot-shaped structures known as volcanic pipes and is characterized by a porphyritic texture containing phenocrysts of olivine and phlogopite within a fine-grained matrix.

Hardness

3-5

Mohs

Luster

Dull

Streak

Gray

Transparency

Opaque

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Kimberlite

Hardness: 3-5
Luster: Dull
Streak: Gray
Transparency: Opaque

Is this kimberlite?

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 kimberlite with a known reference. Kimberlite sits at Mohs 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. Kimberlite leaves a gray streak.
3
Read the luster
Hold the specimen under a strong light. Kimberlite typically shows a dull luster.
4
Match the color range
Compare against the expected color range: dark gray, bluish gray, greenish gray, brown.
5
Look at form & habit
Typical habit: massive.

Often confused with

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

How to tell apart: Peridotite is the harder of the two (Mohs 6-7 vs. 3-5); streak differs, so Kimberlite leaves gray, Peridotite leaves white; luster reads dull on Kimberlite and vitreous to dull on Peridotite.

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Often found alongside kimberlite

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

All properties

Mohs hardness: 3-5
Density: 2.6-2.9 g/cm³
Colors: Dark Gray Bluish Gray Greenish Gray Brown
Streak: Gray
Luster: Dull
Transparency: Opaque
Crystal habit: Massive
Cleavage: None
Rarity: Uncommon
Uses: Collector, Geological Study
Host rock: Volcanic Pipes
Typical price: $10-100 per specimen

Where rockhounds find kimberlite

Classic worldwide localities

Kimberley, South Africa
Yakutia, Russia
Ellendale, Australia
Ekati, Canada
Argyle, Australia

Field-hunting tip

Look in volcanic pipes country, the host setting where kimberlite typically forms. If you start seeing diamond, phlogopite, olivine in float, you are in the right ground. Field specimens usually show a massive habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify kimberlite?+

Mohs hardness is 3-5. It typically shows a dull luster. The streak is gray. Common colors include dark gray, bluish gray, greenish gray, brown.

Where is kimberlite found?+

Notable localities include Kimberley, South Africa; Yakutia, Russia; Ellendale, Australia; Ekati, Canada; Argyle, Australia.

How much is kimberlite worth?+

Typical asking prices fall in the range of $10-100 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like kimberlite?+

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

What minerals are found with kimberlite?+

Kimberlite commonly co-occurs with Diamond, Phlogopite, Olivine, Pyrope Garnet, Diopside, Serpentine. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does kimberlite form in?+

Kimberlite typically forms in volcanic pipes. Working float back to the host body is the standard way to chase a fresh occurrence.

What is kimberlite used for?+

Kimberlite is used in collector, geological study.

Find kimberlite on the map

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