Kasatkinite is an extremely rare barium-calcium borosilicate mineral found in alkaline igneous complexes. It typically presents as colorless to white platy crystals or radiating sprays within quartz-rich matrices.

Hardness

3.5-4

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrare

Kasatkinite

Hardness: 3.5-4
Luster: Vitreous
Streak: White
Transparency: Transparent

No image

Is this kasatkinite?

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 kasatkinite with a known reference. Kasatkinite sits at Mohs 3.5-4 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Kasatkinite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Kasatkinite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: colorless, white, yellowish.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: platy crystals, radiating aggregates.

Often confused with

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

mineral

Stillwellite-(Ce)

Mohs 5

How to tell apart: Stillwellite-(Ce) is the harder of the two (Mohs 5 vs. 3.5-4).

How to tell apart: Barylite is the harder of the two (Mohs 6.5 vs. 3.5-4).

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Often found alongside kasatkinite

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

All properties

Chemical formula: Ba₂Ca₂B₂Si₈O₂₀(OH)₂·7H₂O
Mohs hardness: 3.5-4
Density: 2.81 g/cm³
Colors: Colorless White Yellowish
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Orthorhombic
Crystal habit: Platy Crystals, Radiating Aggregates
Cleavage: Perfect
Rarity: Rare
Uses: Collector
Host rock: Potassic Alkaline Rocks
Typical price: $50-300+ per specimen

Where rockhounds find kasatkinite

Classic worldwide localities

Murun Massif, Russia
Chara-Tokko River basin, Russia

Field-hunting tip

Look in potassic alkaline rocks country — that is the host setting where kasatkinite typically forms. If you start seeing quartz, potassic-feldspar, aegirine in float, you are in the right ground. Field specimens usually show a platy crystals, radiating aggregates habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify kasatkinite?+

Mohs hardness is 3.5-4. It typically shows a vitreous luster. The streak is white. Common colors include colorless, white, yellowish.

Where is kasatkinite found?+

Notable localities include Murun Massif, Russia; Chara-Tokko River basin, Russia.

How much is kasatkinite worth?+

Typical asking prices fall in the range of $50-300+ per specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like kasatkinite?+

Kasatkinite is most often confused with Stillwellite-(Ce), Barylite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with kasatkinite?+

Kasatkinite commonly co-occurs with Quartz, Potassic-feldspar, Aegirine, Tinaksite, Tokkoite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does kasatkinite form in?+

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

What is kasatkinite used for?+

Kasatkinite is used in collector.

Find kasatkinite on the map

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