mineral

Kidney Stone

Nephrolith (typically Calcium Oxalate - CaC2O4)

Hardness: 3-4 Mohs (for calcium varieties). Color: tan, yellow, white, or brown. Luster: dull to crystalline. Structure: monoclinic crystals (Whewellite). Specific gravity: 2.2-2.3.

Hardness: 3-4 Mohs (for calcium varieties)
Color: tan, yellow, white, or brown
Luster: dull to crystalline

Identified June 1, 2026More mineral →

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Physical properties

Hardness: 3-4 Mohs (for calcium varieties). Color: tan, yellow, white, or brown. Luster: dull to crystalline. Structure: monoclinic crystals (Whewellite). Specific gravity: 2.2-2.3.

Formation & geological history

Bio-mineralization process within the human renal system. Formed when minerals in urine become highly concentrated and crystallize. Formed in contemporary biological timeframes.

Uses & applications

Clinical diagnosis and medical research; often kept by individuals as curiosities.

Geological facts

Small stones can pass naturally, but larger ones may require lithotripsy (sound waves) or surgery. They are technically a form of bio-mineralization, much like pearls or seashells.

Field identification & locations

Identified by their jagged, crystalline appearance and presence in urine. Typically found in healthcare settings. Collectors usually only possess their own.

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Arenite (SiO2 based)

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Nephrite Jade

Nephrite

Mineral/Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Biotite Schist

Biotite-rich Schist [K(Mg,Fe)3AlSi3O10(F,OH)2]

metamorphic