Kyawthuite

Real mineral · legendary · BiSbO₄

The rarest mineral on Earth by specimen count. Exactly one crystal is known, discovered in the Mogok gem fields of Myanmar and described as a new species in 2015. Bismuth antimonate of exceptional density. All known properties derive from a single 0.448 gram specimen.

Identity

Formula
BiSbO₄
Chemical class
oxide

Crystallography

Crystal system
orthorhombic
Habits
rounded, massive
Fracture
conchoidal

Physical properties

Mohs hardness
5
Density
8.37 g/cm³
Luster
adamantine
Colors
orange, amber
Streak
pale yellow
Transparency
transparent

Geology

Origins
metamorphic
Host rocks
alluvial deposits
Associated minerals
Spinel, Ruby, Sapphire
Geography
Myanmar (Mogok only)

Classification

Rarity
legendary
Gem quality
Yes

Arcane properties

Affinity
arcane, void
Effects
planar travel, time
Planar origin
Material Plane

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