Yellow Quartzite

Physical Properties

Hardness: 7 on Mohs scale; Color: Yellow, tan, or honey-colored; Luster: Vitreous to dull; Crystal structure: Trigonal (granular texture); Cleavage: None (conchoidal fracture); Specific Gravity: 2.6 - 2.8.

Formation & Geological History

Formed through the metamorphism of quartz-rich sandstone. High heat and pressure cause the quartz grains to recrystallize and fuse together. Often found in Precambrian or Paleozoic metamorphic belts.

Uses & Applications

Used as a decorative stone, in jewelry (cabochons), as an abrasive, and in construction as road ballast or floor tiling.

Geological Facts

Quartzite is so tough that it often outlasts the surrounding rock layers, forming prominent ridges and hills. Yellow coloration is usually caused by iron-oxide staining (limonite) within the crystalline structure.

Field Identification & Locations

Identify by its ability to scratch glass and its granular, sugary appearance on fresh breaks. It is common in riverbeds, glacial deposits, and mountain ranges like the Appalachians or the Rockies.

Identified on: 4/16/2026

Mode: Standard