Clinometaborite is a rare calcium borate mineral known primarily from skarn environments in Japan. It typically occurs as small, clear, tabular monoclinic crystals associated with other calcium-rich minerals in limestone contact zones.

Hardness

3.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrare

Clinometaborite

Hardness: 3.5
Luster: Vitreous
Streak: White
Transparency: Transparent

No image

Is this clinometaborite?

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 clinometaborite with a known reference. Clinometaborite 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. Clinometaborite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Clinometaborite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: colorless, white.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: tabular crystals.

Often confused with

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

mineral

Borax

Mohs 2-2.5

How to tell apart: Clinometaborite is noticeably harder (Mohs 3.5 vs. 2-2.5); luster reads vitreous on Clinometaborite and vitreous to earthy on Borax.

How to tell apart: Luster reads vitreous on Clinometaborite and dull on Priceite.

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Often found alongside clinometaborite

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

All properties

Chemical formula: CaB₃O₄(OH)₃
Mohs hardness: 3.5
Density: 2.42 g/cm³
Colors: Colorless White
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Monoclinic
Crystal habit: Tabular Crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Skarn Deposits
Typical price: varies significantly by specimen availability

Where rockhounds find clinometaborite

Classic worldwide localities

Fuka mine, Okayama Prefecture, Japan

Field-hunting tip

Look in skarn deposits country — that is the host setting where clinometaborite typically forms. If you start seeing calcite, bultfonteinite, tobermorite in float, you are in the right ground. Field specimens usually show a tabular crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify clinometaborite?+

Mohs hardness is 3.5. It typically shows a vitreous luster. The streak is white. Common colors include colorless, white.

Where is clinometaborite found?+

Notable localities include Fuka mine, Okayama Prefecture, Japan.

How much is clinometaborite worth?+

Typical asking prices fall in the range of varies significantly by specimen availability. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like clinometaborite?+

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

What minerals are found with clinometaborite?+

Clinometaborite commonly co-occurs with Calcite, Bultfonteinite, Tobermorite, Scawtite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does clinometaborite form in?+

Clinometaborite typically forms in skarn deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is clinometaborite used for?+

Clinometaborite is used in collector.

Find clinometaborite on the map

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