Smoky Quartz (Faceted Beads)

Physical Properties

Hardness: 7 on Mohs scale; Color: Brownish-grey to black (smoky); Luster: Vitreous; Crystal Structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65.

Formation & Geological History

Formed in igneous or metamorphic rocks (especially pegmatites and hydrothermal veins) through natural irradiation of aluminum-bearing quartz over millions of years.

Uses & Applications

Primarily used in jewelry, lapidary arts, and as a collector's specimen. In industry, quartz is used for its piezoelectric properties and in glass making.

Geological Facts

The 'smoky' color comes from free silicon formed from the silicon dioxide by natural irradiation. It is the national gem of Scotland, where it is often called 'Cairngorm' after the mountain range.

Field Identification & Locations

Identify by its brownish translucent color, Mohs hardness of 7 (harder than glass), and lack of cleavage. Common in many terrains, particularly granite-rich regions like the Alps or Colorado.

Identified on: 4/20/2026

Mode: Standard