Tsepinite-Ca is a rare member of the labuntsovite group, typically occurring as small, elongated prismatic crystals in alkaline igneous environments. Collectors prize it for its specific chemical composition and occurrence within the complex mineral assemblages of the Khibiny alkaline massif.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrareLabuntsovite Group family

Tsepinite-Ca

Hardness: 5
Luster: Vitreous
Streak: White
Transparency: Translucent

No image

Is this tsepinite-ca?

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 tsepinite-ca with a known reference. Tsepinite-Ca sits at Mohs 5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Tsepinite-Ca leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Tsepinite-Ca typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: yellow, brown, colorless.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: prismatic crystals.

Often confused with

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

Often found alongside tsepinite-ca

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

All properties

Chemical formula: (Ca,Na,K,◻)₄(Ti,Nb)₄(Si₄O₁₂)₂(OH,O)₄·5H₂O
Mohs hardness: 5
Density: 2.8 g/cm³
Colors: Yellow Brown Colorless
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Monoclinic
Crystal habit: Prismatic Crystals
Cleavage: Distinct
Rarity: Rare
Uses: Collector
Host rock: Alkaline Pegmatites
Typical price: $50-300 per specimen

Where rockhounds find tsepinite-ca

Classic worldwide localities

Kola Peninsula, Russia
Khibiny Massif, Russia

Field-hunting tip

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

Common questions

How do you identify tsepinite-ca?+

Mohs hardness is 5. It typically shows a vitreous luster. The streak is white. Common colors include yellow, brown, colorless.

Where is tsepinite-ca found?+

Notable localities include Kola Peninsula, Russia; Khibiny Massif, Russia.

How much is tsepinite-ca 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 tsepinite-ca?+

Tsepinite-Ca is most often confused with Nenadkevichite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with tsepinite-ca?+

Tsepinite-Ca 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 tsepinite-ca form in?+

Tsepinite-Ca typically forms in alkaline pegmatites. Working float back to the host body is the standard way to chase a fresh occurrence.

What is tsepinite-ca used for?+

Tsepinite-Ca is used in collector.

Find tsepinite-ca on the map

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