Carmichaelite is a rare titanium chromium iron hydroxide, typically cinnamon brown to black. It occurs as microscopic inclusions in mantle-derived pyrope crystals carried up in kimberlite.

Hardness

Mohs

Luster

Metallic

Transparency

Transparent

mineralrare

Carmichaelite

Carmichaelite is a rare titanium chromium iron hydroxide, typically cinnamon brown to black. It occurs as microscopic inclusions in mantle-derived pyrope crystals carried up in kimberlite.

Hardness: 6
Luster: Metallic
Transparency: Transparent

No image

Is this carmichaelite?

4-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 carmichaelite with a known reference. Carmichaelite sits at Mohs 6, softer than the next harder reference, harder than the previous one.
2
Read the luster
Hold the specimen under a strong light. Carmichaelite typically shows a metallic luster.
3
Match the color range
Compare against the expected color range: cinnamon brown, black.
4
Look at form & habit
Crystal system: monoclinic. Typical habit: microscopic inclusions in mantle-derived pyrope.

Often confused with

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

mineral

Rutile

Mohs 6-6.5

How to tell apart: Luster reads metallic on Carmichaelite and metallic to adamantine on Rutile.

How to tell apart: Luster reads metallic on Carmichaelite and submetallic on Manaccanite.

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Often found alongside carmichaelite

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

All properties

Chemical formula: (Ti,Cr,Fe)(O,OH)₂
Mohs hardness: 6
Density: 3.95 g/cm³
Colors: Cinnamon Brown Black
Luster: Metallic
Transparency: Transparent
Crystal system: Monoclinic
Crystal habit: Microscopic Inclusions in Mantle-derived Pyrope
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Volcanic Xenoliths

Where rockhounds find carmichaelite

Classic worldwide localities

Garnet Ridge, an ultramafic diatreme on the Colorado Plateau in Arizona, USA

Field-hunting tip

Look in volcanic xenoliths country, the host setting where carmichaelite typically forms. If you start seeing corundum, spinel, ilmenite in float, you are in the right ground. Field specimens usually show a microscopic inclusions in mantle-derived pyrope habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify carmichaelite?+

Mohs hardness is 6. It typically shows a metallic luster. Common colors include cinnamon brown, black.

Where is carmichaelite found?+

Notable localities include Garnet Ridge, an ultramafic diatreme on the Colorado Plateau in Arizona, USA.

What rocks look like carmichaelite?+

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

What minerals are found with carmichaelite?+

Carmichaelite commonly co-occurs with Corundum, Spinel, Ilmenite, Zircon. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does carmichaelite form in?+

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

What is carmichaelite used for?+

Carmichaelite is used in collector.

Find carmichaelite on the map

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