Quartz with Hematite Staining

Physical Properties

Hardness: 7 on Mohs scale; Color: Milky white to grey with reddish-brown staining; Luster: Vitreous to dull; Crystal structure: Trigonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65.

Formation & Geological History

Formed via hydrothermal activity where silica-rich fluids cooled in veins or cavities. The reddish-brown color comes from the oxidation of iron-bearing minerals (Hematite) within or on the surface of the quartz.

Uses & Applications

Primarily collected as mineral specimens; higher quality clear quartz is used in electronics and glass manufacturing, while stained pieces like this are common in amateur rock collections.

Geological Facts

Iron is one of the most common causes of coloration in minerals. Even a tiny amount of hematite can stain a large quartz vein deep red or orange, often referred to as 'ferruginous quartz'.

Field Identification & Locations

Identified in the field by its hardness (scratches glass), lack of cleavage, and the characteristic rusty-red staining. Common in quartz veins globally, especially in areas with significant weathering of iron minerals.

Identified on: 5/2/2026

Mode: Standard