Mineral (Biogenic)

Kidney Stone (Medical Specimen)

Calcium oxalate monohydrate (Whewellite) / CaC2O4·H2O

AI-generated identification · may be incorrect

Hardness: 2.5 - 3.0 on Mohs scale; Color: Brown, tan, or yellowish; Luster: Earthy to dull; Structure: Crystalline or granular with 'mulberry' spiky surface texture; Cleavage: None.

Hardness: 2
Color: Brown, tan, or yellowish
Luster: Earthy to dull

Identified April 3, 2026More mineral (biogenic) →

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Physical properties

Hardness: 2.5 - 3.0 on Mohs scale; Color: Brown, tan, or yellowish; Luster: Earthy to dull; Structure: Crystalline or granular with 'mulberry' spiky surface texture; Cleavage: None.

Formation & geological history

Formed through the precipitation of minerals and acid salts out of concentrated urine within the renal system. This specimen appears to be a calcium oxalate 'mulberry' stone.

Uses & applications

Primarily used for medical analysis (pathology) to determine dietary or metabolic causes; sometimes kept as a novelty specimen by the patient.

Geological facts

Kidney stones have been found in Egyptian mummies dating back over 7,000 years. The 'mulberry' shape seen here is characteristic of calcium oxalate monohydrate.

Field identification & locations

Identify by its distinctive jagged/spiky exterior and dark brown color. In the 'field' (medical context), it is collected through straining urine after renal colic symptoms.