Gold Ore

Physical Properties

Hardness: 2.5-3 (Gold), 7 (Quartz host). Color: Yellow-gold flecks, rusty orange-brown (limonite/iron oxidation), and metallic grey (sulfides). Luster: Metallic to vitreous. Crystal structure: Sub-microscopic to visible isometric grains.

Formation & Geological History

Formed from hydrothermal fluids circulating through fractures in the Earth's crust, often associated with volcanic activity and tectonic plate boundaries. Fluids deposit gold alongside quartz and sulfides like pyrite.

Uses & Applications

Primary source of elemental gold for investment, jewelry, electronics, and dentistry. Collected as high-grade geological specimens.

Geological Facts

Most gold is recovered from ore that contains only a few grams per ton, whereas 'nugget' ore like this is significantly richer. Visible gold in a hand specimen is quite rare.

Field Identification & Locations

Identify by high specific gravity and softness of metallic yellow flecks (gold will dent rather than shatter). Look for quartz veins with iron staining (gossan) in mountainous or volcanic terrain.

Identified on: 4/22/2026

Mode: Standard