Tarbagataite is a rare member of the eudialyte group typically found in alkaline pegmatites. It forms small, tabular, yellow-to-brown crystals often associated with microcline and aegirine in agpaitic environments.

Hardness

5-6

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrareEudialyte Group family

Tarbagataite

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

No image

Is this tarbagataite?

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 tarbagataite with a known reference. Tarbagataite 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. Tarbagataite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Tarbagataite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: yellow, yellow-brown, brown.
5
Look at form & habit
Crystal system: trigonal. Typical habit: tabular crystals.

Often confused with

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

Often found alongside tarbagataite

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

All properties

Chemical formula: (K,Na,Sr)₄Zr₂TiSi₈O₂₂F₂·H₂O
Mohs hardness: 5-6
Density: 2.95-3.00 g/cm³
Colors: Yellow Yellow-brown Brown
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Trigonal
Crystal habit: Tabular Crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Alkaline Pegmatites
Typical price: $50-300 per specimen

Where rockhounds find tarbagataite

Classic worldwide localities

Tarbagatai Mountains, Kazakhstan

Field-hunting tip

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

Common questions

How do you identify tarbagataite?+

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

Where is tarbagataite found?+

Notable localities include Tarbagatai Mountains, Kazakhstan.

How much is tarbagataite 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 tarbagataite?+

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

What minerals are found with tarbagataite?+

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

What kind of rock does tarbagataite form in?+

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

What is tarbagataite used for?+

Tarbagataite is used in collector.

Find tarbagataite on the map

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