Quartz Vein in Host Rock

Physical Properties

Hardness: 7 (quartz components); Color: White, tan, and brown; Luster: Vitreous to dull; Crystal structure: Trigonal (hexagonal); Cleavage: None/Conchoidal fracture; Specific gravity: ~2.65

Formation & Geological History

Formed through hydrothermal processes where silica-rich fluids permeate cracks in existing rock (the brown matrix) and crystallize over time, often during mountain-building events or volcanic activity.

Uses & Applications

Used primarily as decorative garden stone, geological teaching specimens, or for extracting high-purity silica for industrial use if found in large enough deposits.

Geological Facts

Quartz veins are often the primary source of 'lode gold,' as gold particles frequently deposit in the same hydrothermal fractures as the quartz.

Field Identification & Locations

Identify in the field by looking for white, glassy bands or inclusions within darker, duller rock. Quartz will easily scratch glass and will not react with acid (unlike calcite).

Identified on: 4/19/2026

Mode: Standard