Vaterite is a rare polymorph of calcium carbonate that is metastable under ambient conditions, often transforming into calcite or aragonite over time. It is frequently identified in nature as microscopic spherulitic aggregates within sedimentary environments or associated with biogenic minerals in organisms.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Semitransparent

mineralrareCalcite family

Vaterite

Hardness: 3
Luster: Vitreous
Streak: White
Transparency: Semitransparent

Is this vaterite?

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 vaterite with a known reference. Vaterite sits at Mohs 3, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Streak: white.
3
Read the luster
Hold the specimen under a strong light. Luster: vitreous.
4
Match the color range
Compare against the expected color range: colorless.
5
Look at form & habit
Crystal system: hexagonal. Typical habit: spherulitic.

Often confused with

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

Often found alongside vaterite

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

All properties

Chemical formula: CaCO₃
Mohs hardness: 3
Density: 2.54 g/cm³
Colors: Colorless
Streak: White
Luster: Vitreous
Transparency: Semitransparent
Crystal system: Hexagonal
Crystal habit: Spherulitic
Cleavage: Good
Rarity: Rare
Uses: Collector, Scientific research
Host rock: A major constituent of a carbonated calcium silicate hydrogel complex formed from larnite (Ballycraigy, Ireland)

Where rockhounds find vaterite

Classic worldwide localities

Ballycraigy, Larne, Co. Antrim, Ireland
Bellerberg and Emmelberg volcanoes, Eifel district, Germany
Hopffeldboden, Salzburg, Austria
Mont Saint-Hilaire, Quebec, Canada
Wessels mine, near Kuruman, Cape Province, South Africa
Hatrurim Formation, Israel

Field-hunting tip

Where it forms: A major constituent of a carbonated calcium silicate hydrogel complex formed from larnite (Ballycraigy, Ireland). If you start seeing calcite, aragonite, tobermorite in float, you are in the right ground. Typical habit: spherulitic. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify vaterite?+

Mohs hardness is 3. Luster: vitreous. The streak is white. Common colors include colorless.

Where is vaterite found?+

Notable localities include Ballycraigy, Larne, Co. Antrim, Ireland; Bellerberg and Emmelberg volcanoes, Eifel district, Germany; Hopffeldboden, Salzburg, Austria; Mont Saint-Hilaire, Quebec, Canada; Wessels mine, near Kuruman, Cape Province, South Africa.

What rocks look like vaterite?+

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

What minerals are found with vaterite?+

Vaterite commonly co-occurs with Calcite, Aragonite, Tobermorite, Hydrogarnet, Kaolinite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does vaterite form in?+

Where it forms: A major constituent of a carbonated calcium silicate hydrogel complex formed from larnite (Ballycraigy, Ireland). Working float back to the host body is the standard way to chase a fresh occurrence.

What is vaterite used for?+

Vaterite is used in collector, scientific research.

Find vaterite on the map

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