Sandstone (Banded)

Clastic Sedimentary Rock (primarily Quartz, SiO2)

Rock Type: sedimentary

Sandstone (Banded)

Physical Properties

Hardness: 6-7 on Mohs scale; Color: Tan, brown, and cream bands; Luster: Dull/Earthy; Crystal structure: Granular (clastic); Cleavage: None; Specific gravity: 2.2-2.8

Formation & Geological History

Formed from the accumulation and cementation of sand-sized mineral grains or rock fragments over millions of years. The banding (Liesegang rings) is caused by the precipitation of iron oxides from groundwater.

Uses & Applications

Used primarily in construction (dimension stone), landscaping, decorative carving, and as sandpaper abrasives. High-quality banded specimens are used in lapidary for cabochons and home decor.

Geological Facts

Sandstone makes up about 20-25% of all sedimentary rocks on Earth. The distinct banding seen here is often mistaken for wood grain or fossilized material, but it is actually a chemical precipitation pattern.

Field Identification & Locations

Identify in the field by its gritty texture (feels like sandpaper) and visible layers. It is ubiquitous in arid climates and riverbeds. Collectors should look for unique rhythmic banding patterns.

Identified on: 4/15/2026

Mode: Standard