Kolskyite is a rare sodium calcium titanium silicate primarily found in the hyperalkaline complexes of the Kola Peninsula. It typically occurs as pinkish yellow, platy tabular crystals embedded within pegmatite matrices, often requiring careful microscopic identification due to its close relationship with the lomonosovite group.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrareLomonosovite Group family

Kolskyite

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

No image

Is this kolskyite?

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 kolskyite with a known reference. Kolskyite 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: pinkish yellow.
5
Look at form & habit
Crystal system: triclinic. Typical habit: platy crystals, tabular aggregates.

Often confused with

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

mineral

Lomonosovite

Mohs 3-4

How to tell apart: Streak differs, so Kolskyite leaves white, Lomonosovite leaves light rose-cinnamon.

Often found alongside kolskyite

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

All properties

Chemical formula: Na₂CaTi₄(Si₂O₇)₂O₄(H₂O)₇
Mohs hardness: 3
Density: 2.509 g/cm³
Colors: Pinkish yellow
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Triclinic
Crystal habit: Platy crystals, tabular aggregates
Cleavage: Perfect on {001}
Rarity: Rare
Uses: Collector
Host rock: Formed in a pegmatite as a result of hydrothermal activity

Where rockhounds find kolskyite

Classic worldwide localities

Kirovskii mine (+252 m level), Mount Kukisvumchorr, Khibiny alkaline massif, Kola Peninsula, Russia

Field-hunting tip

Where it forms: Formed in a pegmatite as a result of hydrothermal activity. If you start seeing natrolite, nechelyustovite, kazanskyite in float, you are in the right ground. Typical habit: platy crystals, tabular aggregates. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify kolskyite?+

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

Where is kolskyite found?+

Notable localities include Kirovskii mine (+252 m level), Mount Kukisvumchorr, Khibiny alkaline massif, Kola Peninsula, Russia.

What rocks look like kolskyite?+

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

What minerals are found with kolskyite?+

Kolskyite commonly co-occurs with Natrolite, Nechelyustovite, Kazanskyite, Barytolamprophyllite, Hydroxylapatite, Belovite-. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does kolskyite form in?+

Where it forms: Formed in a pegmatite as a result of hydrothermal activity. Working float back to the host body is the standard way to chase a fresh occurrence.

What is kolskyite used for?+

Kolskyite is used in collector.

Find kolskyite on the map

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