sedimentary

Feldspathic sandstone or arkose

Arkose; chiefly quartz (SiO₂), potassium feldspar (KAlSi₃O₈), and minor lithic grains in a silica/clay cement

AI-generated identification · may be incorrect

Coarse, poorly sorted granular texture with conspicuous pale feldspar fragments; tan-beige color, dull to slightly sandy luster, no obvious cleavage as a rock. Individual quartz grains are Mohs 7 and feldspar about 6; bulk density is commonly ~2.2–2.6 g/cm³.

Identified August 13, 2026More sedimentary →

Explore Feldspathic sandstone or arkose in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

At a glance

Common name: Feldspathic sandstone or arkose
Scientific name: Arkose; chiefly quartz (SiO₂), potassium feldspar (KAlSi₃O₈), and minor lithic grains in a silica/clay cement
Category: sedimentary
Identified: August 13, 2026
Method: Standard

AI Estimated Value

Typically $1–$10 for a common hand specimen; higher only if exceptionally attractive, rare, or provenance-documented.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Formed when weathered granite or gneiss was rapidly eroded, transported a short distance, and lithified by burial and cementation. Its age cannot be determined from the photograph and may range from Precambrian to recent geological periods.

Uses & applications

Used locally as building stone, aggregate, and sometimes decorative stone; ordinary pieces have little jewelry value.

Geological facts

The abundant angular, light-colored grains and granitic appearance distinguish arkose from mature quartz sandstone. A dilute acid test usually produces little or no fizz unless carbonate cement is present.

Field identification & locations

Common in alluvial fans, river channels, and basins adjacent to granitic uplands; major occurrences exist worldwide. Examine a fresh surface with a hand lens and test grain hardness rather than judging only by color.