Ferruginous Quartz

Physical Properties

Hardness: 7 (Mohs), Color: Translucent yellow to orange-brown, Luster: Vitreous to waxy, Crystal Structure: Trigonal/Hexagonal, Cleavage: None/Conchoidal fracture, Specific Gravity: 2.65

Formation & Geological History

Formed through hydrothermal processes or within igneous rocks where micro-crystalline or macro-crystalline quartz was exposed to mineral-rich waters. The yellow-orange tint is caused by traces of limonite or hematite staining the surface or cracks of the quartz crystal.

Uses & Applications

Commonly used for lapidary work, specimen collecting, metaphysical practices, and occasionally crushed for industrial abrasives.

Geological Facts

Also sometimes called 'Yellow Quartz' or 'Golden Quartz'. Unlike Citrine, which is colored by iron within the crystal lattice, Ferruginous Quartz is typically colored by iron oxide inclusions or coatings. It is one of the most common mineral varieties found in riverbeds.

Field Identification & Locations

Identify by its hardness (will scratch glass), translucent appearance, and yellow-gold tint. Look in riverbeds, gravel pits, and mountain runoff areas. Collectors look for pieces with high clarity or interesting iron-oxide patterns.

Identified on: 4/27/2026

Mode: Standard