Kalborsite is a rare phyllosilicate mineral found primarily in alkaline pegmatites and nepheline syenites. Collectors look for its characteristic tetragonal prismatic crystals that often form in tight associations with other rare-earth minerals in the Kola Peninsula regions.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrare

Kalborsite

Hardness: 6
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this kalborsite?

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 kalborsite with a known reference. Kalborsite sits at Mohs 6, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Kalborsite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Kalborsite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: white, colorless.
5
Look at form & habit
Crystal system: tetragonal. Typical habit: prismatic crystals.

Often confused with

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

mineral

Quartz

Mohs 7

How to tell apart: Quartz is the harder of the two (Mohs 7 vs. 6).

Often found alongside kalborsite

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

All properties

Chemical formula: K₆Al₄Be₂Si₆O₂₀(OH)₄F
Mohs hardness: 6
Density: 2.49 g/cm³
Colors: White Colorless
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Tetragonal
Crystal habit: Prismatic Crystals
Cleavage: Poor
Rarity: Rare
Uses: Collector
Host rock: Alkaline Igneous Rocks
Typical price: $50-300 per specimen

Where rockhounds find kalborsite

Classic worldwide localities

Khibiny Massif, Kola Peninsula, Russia
Lovozero Massif, Kola Peninsula, Russia

Field-hunting tip

Look in alkaline igneous rocks country, the host setting where kalborsite typically forms. If you start seeing microcline, aegirine, 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 kalborsite?+

Mohs hardness is 6. It typically shows a vitreous luster. The streak is white. Common colors include white, colorless.

Where is kalborsite found?+

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

How much is kalborsite 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 kalborsite?+

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

What minerals are found with kalborsite?+

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

What kind of rock does kalborsite form in?+

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

What is kalborsite used for?+

Kalborsite is used in collector.

Find kalborsite on the map

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