Cabvinite is a rare thorium hydroxide that forms white square prismatic crystals. It occurs in low-temperature hydrothermal alteration of Mo-Bi mineralization. It was first described from Mo-Bi ore deposit of Su Seinargiu, Sarroch, Cagliari, Sardinia, Italy.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrare

Cabvinite

Hardness: 4
Luster: Vitreous
Streak: White
Transparency: Transparent

No image

Is this cabvinite?

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 cabvinite with a known reference. Cabvinite 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. Cabvinite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Cabvinite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: white.
5
Look at form & habit
Crystal system: tetragonal. Typical habit: square prismatic crystals.

Often confused with

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

How to tell apart: Luster reads vitreous on Cabvinite and vitreous to pearly on Apophyllite.

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Often found alongside cabvinite

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

All properties

Chemical formula: Th₂F₇(OH)·3H₂O
Mohs hardness: 4
Density: 5.35 g/cm³
Colors: White
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Tetragonal
Crystal habit: Square Prismatic Crystals
Cleavage: Cleavage or Parting On {001}, Suggested By SEM Images
Rarity: Rare
Uses: Collector
Host rock: Alkaline Igneous Rocks

Where rockhounds find cabvinite

Classic worldwide localities

Mo-Bi ore deposit of Su Seinargiu, Sardinia, Italy

Field-hunting tip

Look in alkaline igneous rocks country, the host setting where cabvinite typically forms. If you start seeing aegirine, microcline, nepheline in float, you are in the right ground. Field specimens usually show a square prismatic crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify cabvinite?+

Mohs hardness is 4. It typically shows a vitreous luster. The streak is white. Common colors include white.

Where is cabvinite found?+

Notable localities include Mo-Bi ore deposit of Su Seinargiu, Sardinia, Italy.

Is cabvinite safe to handle?+

This mineral is radioactive. Contains thorium and is radioactive; store it apart from other specimens. Wash hands thoroughly after handling and avoid creating dust. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like cabvinite?+

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

What minerals are found with cabvinite?+

Cabvinite commonly co-occurs with Aegirine, Microcline, Nepheline, Eudialyte. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does cabvinite form in?+

Cabvinite typically forms in alkaline igneous rocks. Working float back to the host body is the standard way to chase a fresh occurrence.

What is cabvinite used for?+

Cabvinite is used in collector.

Find cabvinite on the map

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