Sedimentary

Painted River Rock

Anthropogenic-modified Siliciclastic Sedimentary Rock

Hardness: 6-7 (Mohs scale for the base rock); Color: Teal, black, and white (applied paint); Luster: Matte or acrylic; Structure: Rounded/ellipsoid (clastic texture); Specific Gravity: 2.6-2.7 (typical for sandstone or limestone base).

Hardness: 6-7 (Mohs scale for the base rock)
Color: Teal, black, and white (applied paint)
Luster: Matte or acrylic

Identified March 22, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through thousands of years of fluvial (river) erosion and weathering of larger rock formations, subsequently modified by modern human activity within the last 10-20 years through the application of synthetic pigments.

Uses & applications

Hobbyist craft, decorative garden art, 'kindness rock' projects, and as a plaything or memento.

Geological facts

This specimen is part of a global trend known as 'The Kindness Rocks Project' where people paint rocks to leave for others to find. This specific specimen features a pareidolic 'sad face' design.

Field identification & locations

Identify in the field by looking for unnatural colors or geometric patterns on rounded cobbles. Often found in public parks, gardens, or urban landscaping. For collectors, seek smooth surfaces that take paint well.

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