mineral

Kidney Stone (Renal Calculus)

Calcium oxalate monohydrate (Whewellite) / CaC2O4·H2O

AI-generated identification · may be incorrect

Hardness: Approx 2.5-3 (Mohs). Color: Brown, tan, or grey. Luster: Dull to earthy. Crystal structure: Monoclinic. Cleavage: Poor. Specific gravity: Approx 2.2.

Hardness: Approx 2
Color: Brown, tan, or grey
Luster: Dull to earthy

Identified April 11, 2026More mineral →

Explore Kidney Stone (Renal Calculus) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: Approx 2.5-3 (Mohs). Color: Brown, tan, or grey. Luster: Dull to earthy. Crystal structure: Monoclinic. Cleavage: Poor. Specific gravity: Approx 2.2.

Formation & geological history

Formed through the precipitation and crystallization of minerals (usually calcium oxalate) within the human kidney over months or years, often due to dehydration or metabolic imbalances.

Uses & applications

Medical diagnostic value; primarily analyzed in clinical laboratories to determine physiological causes of stone formation.

Geological facts

Kidney stones are biological minerals. While they are not formed in mother Earth, they are chemically and structurally identical to geological whewellite crystals found in carbonaceous veins.

Field identification & locations

Identify by its irregular, often jagged 'burr' shape and granular surface. Common in individuals with high dietary oxalate intake or low fluid intake.