Sandstone

Physical Properties

Hardness: 6-7 (on Mohs scale if quartz-rich); Color: Tan, beige, grey, and yellow with visible metallic grains (likely pyrite); Luster: Dull/Earthy with vitreous sparkles; Crystal structure: Clastic (granular); Cleavage: None.

Formation & Geological History

Formed through the accumulation and cementation of sand-sized mineral grains or rock fragments over millions of years, typically in river beds, beaches, or desert environments.

Uses & Applications

Used widely in construction as a building material, decorative stone, and in the manufacturing of glass and grindstones.

Geological Facts

Sandstone can be a significant reservoir for groundwater, oil, and natural gas due to its porosity. The presence of yellow/gold specks in this specimen suggests mineralization, possibly pyrite ('Fool's Gold').

Field Identification & Locations

Identify in the field by its gritty 'sandpaper' feel and visible grains. Often found in riverbeds or near coastal cliffs. Look for layering (bedding) or cross-bedding features.

Identified on: 4/21/2026

Mode: Standard