Liddicoatite is a rare calcium-rich member of the tourmaline group, famous for its intense and complex color zoning often forming 'geometric' or 'star' patterns in cross-section. It is typically found in granitic pegmatites and is highly prized by collectors for its aesthetic crystal habits and vibrant multi-colored interior displays.

Hardness

7.5

Mohs

Luster

Vitreous on fractures

Streak

Very light brown

Transparency

Transparent to translucent

mineralrareTourmaline Group family

Liddicoatite

Hardness: 7.5
Luster: Vitreous on fractures
Streak: Very light brown
Transparency: Transparent to translucent

Is this liddicoatite?

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 liddicoatite with a known reference. Liddicoatite sits at Mohs 7.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Streak: very light brown.
3
Read the luster
Hold the specimen under a strong light. Luster: vitreous on fractures.
4
Match the color range
Compare against the expected color range: pink, red, green, blue, brown, colorless.
5
Look at form & habit
Crystal system: trigonal. Typical habit: prismatic, triangular crystals.

Often confused with

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

mineral

Elbaite

Mohs 7

How to tell apart: Streak differs, so Liddicoatite leaves very light brown, Elbaite leaves white.

How to tell apart: Streak differs, so Liddicoatite leaves very light brown, Dravite leaves light brown, white.

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Often found alongside liddicoatite

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

All properties

Chemical formula: Ca(Li₂Al)Al₆(Si₆O₁₈)(BO₃)₃(OH)₃(OH)
Mohs hardness: 7.5
Density: 3.02 g/cm³
Colors: Pink Red Green Blue Brown Colorless
Streak: Very light brown
Luster: Vitreous on fractures
Transparency: Transparent to translucent
Crystal system: Trigonal
Crystal habit: Prismatic, triangular crystals
Cleavage: Poor on {0001}
Rarity: Rare
Uses: Collector, Gemstone
Host rock: Detrital in soil, an apparent product of the local pegmatites

Where rockhounds find liddicoatite

Classic worldwide localities

Antsirabe, Tsilaizina, and Anjanabonoina, Madagascar

Field-hunting tip

Where it forms: Detrital in soil, an apparent product of the local pegmatites. If you start seeing quartz, elbaite, albite in float, you are in the right ground. Typical habit: prismatic, triangular crystals. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify liddicoatite?+

Mohs hardness is 7.5. Luster: vitreous on fractures. The streak is very light brown. Common colors include pink, red, green, blue.

Where is liddicoatite found?+

Notable localities include Antsirabe, Tsilaizina, and Anjanabonoina, Madagascar.

What rocks look like liddicoatite?+

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

What minerals are found with liddicoatite?+

Liddicoatite commonly co-occurs with Quartz, Elbaite, Albite, Micas. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does liddicoatite form in?+

Where it forms: Detrital in soil, an apparent product of the local pegmatites. Working float back to the host body is the standard way to chase a fresh occurrence.

What is liddicoatite used for?+

Liddicoatite is used in collector, gemstone.

Find liddicoatite on the map

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