Koashvite is a rare member of the eudialyte group found primarily in the agpaitic alkaline rocks of the Kola Peninsula. It typically occurs as reddish, tabular crystals embedded within pegmatitic zones of nepheline syenites. Collectors look for its characteristic trigonal symmetry and association with other rare-earth-bearing silicate minerals.

Hardness

5-6

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrareEudialyte Group family

Koashvite

Hardness: 5-6
Luster: Vitreous
Streak: White
Transparency: Translucent

No image

Is this koashvite?

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 koashvite with a known reference. Koashvite sits at Mohs 5-6 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Koashvite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Koashvite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: red, brownish-red, yellow-brown.
5
Look at form & habit
Crystal system: trigonal. Typical habit: tabular crystals, massive, granular.

Often confused with

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

Often found alongside koashvite

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

All properties

Chemical formula: (Na,Ca)₆(Fe,Mn)(Zr,Ti)Si₆(O,OH,F)₁₈(Cl,OH)
Mohs hardness: 5-6
Density: 2.95-3.05 g/cm³
Colors: Red Brownish-red Yellow-brown
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Trigonal
Crystal habit: Tabular Crystals, Massive, Granular
Cleavage: Poor
Rarity: Rare
Uses: Collector, Scientific Research
Host rock: Alkaline Pegmatites and Nepheline Syenites
Typical price: $50-300 per specimen depending on size and quality

Where rockhounds find koashvite

Classic worldwide localities

Khibiny Massif (Kola Peninsula, Russia)
Lovozero Massif (Kola Peninsula, Russia)

Field-hunting tip

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

Common questions

How do you identify koashvite?+

Mohs hardness is 5-6. It typically shows a vitreous luster. The streak is white. Common colors include red, brownish-red, yellow-brown.

Where is koashvite found?+

Notable localities include Khibiny Massif (Kola Peninsula, Russia); Lovozero Massif (Kola Peninsula, Russia).

How much is koashvite worth?+

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

What rocks look like koashvite?+

Koashvite is most often confused with Eudialyte, Kentbrooksite, Alluaivite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with koashvite?+

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

What kind of rock does koashvite form in?+

Koashvite typically forms in alkaline pegmatites and nepheline syenites. Working float back to the host body is the standard way to chase a fresh occurrence.

What is koashvite used for?+

Koashvite is used in collector, scientific research.

Find koashvite on the map

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