Kyawthuite is currently recognized as the rarest mineral in the world, with only a single documented specimen discovered in the Mogok Valley of Myanmar. It is a bismuth antimony oxide forming small, orange, transparent tabular crystals that show exceptional luster.

Hardness

5.5

Mohs

Luster

Sub-adamantine

Streak

White

Transparency

Transparent

mineralrare

Kyawthuite

Hardness: 5.5
Luster: Sub-adamantine
Streak: White
Transparency: Transparent

Is this kyawthuite?

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 kyawthuite with a known reference. Kyawthuite sits at Mohs 5.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Kyawthuite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Kyawthuite typically shows a sub-adamantine luster.
4
Match the color range
Compare against the expected color range: orange, reddish-orange.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: small tabular crystals.

Often confused with

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

mineral

Mopungite

Mohs 3

How to tell apart: Kyawthuite is noticeably harder (Mohs 5.5 vs. 3); luster reads sub-adamantine on Kyawthuite and vitreous on Mopungite.

How to tell apart: Streak differs, so Kyawthuite leaves white, Tripuhyite leaves yellow.

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Often found alongside kyawthuite

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

All properties

Chemical formula: Bi³⁺Sb⁵⁺O₄
Mohs hardness: 5.5
Density: 8.25 g/cm³
Colors: Orange Reddish-orange
Streak: White
Luster: Sub-adamantine
Transparency: Transparent
Crystal system: Monoclinic
Crystal habit: Small Tabular Crystals
Cleavage: None Reported
Rarity: Rare
Uses: Collector
Host rock: Alluvial Deposits of The Mogok Metamorphic Belt
Typical price: Extremely high, unique market pricing for the rarest mineral in the world.

Where rockhounds find kyawthuite

Classic worldwide localities

Mogok, Myanmar

Field-hunting tip

Look in alluvial deposits of the mogok metamorphic belt country, the host setting where kyawthuite typically forms. If you start seeing quartz, topaz, beryl in float, you are in the right ground. Field specimens usually show a small tabular crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify kyawthuite?+

Mohs hardness is 5.5. It typically shows a sub-adamantine luster. The streak is white. Common colors include orange, reddish-orange.

Where is kyawthuite found?+

Notable localities include Mogok, Myanmar.

How much is kyawthuite worth?+

Typical asking prices fall in the range of Extremely high, unique market pricing for the rarest mineral in the world.. Quality, size, and provenance can move individual specimens well outside that range.

Is kyawthuite safe to handle?+

It contains toxic constituents. Contains Bismuth and Antimony. Handle with care, wash hands thoroughly after handling, and avoid ingestion or inhalation of dust. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like kyawthuite?+

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

What minerals are found with kyawthuite?+

Kyawthuite commonly co-occurs with Quartz, Topaz, Beryl, Feldspar. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does kyawthuite form in?+

Kyawthuite typically forms in alluvial deposits of the mogok metamorphic belt. Working float back to the host body is the standard way to chase a fresh occurrence.

What is kyawthuite used for?+

Kyawthuite is used in collector.

Find kyawthuite on the map

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