Mineral

Gold Ore (Auriferous Quartz with Chalcopyrite/Pyrite)

Au (Native Gold) in Quartz (SiO2) with FeS2 (Pyrite) or CuFeS2 (Chalcopyrite)

Hardness: 2.5-3 (Gold) vs 7 (Quartz); Color: Brass-yellow or golden streaks on reddish-brown matrix; Luster: Metallic; Crystal Structure: Isometric (Sulfides); Specific Gravity: 19.3 (Pure Gold)

Hardness: 2
Color: Brass-yellow or golden streaks on reddish-brown matrix
Luster: Metallic

Identified May 18, 2026More mineral →

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Physical properties

Hardness: 2.5-3 (Gold) vs 7 (Quartz); Color: Brass-yellow or golden streaks on reddish-brown matrix; Luster: Metallic; Crystal Structure: Isometric (Sulfides); Specific Gravity: 19.3 (Pure Gold)

Formation & geological history

Formed via hydrothermal processes where mineral-rich hot fluids circulate through fractures in the earth's crust, often associated with volcanic activity or mountain building.

Uses & applications

Primary source for commercial gold extraction; highly valued for mineral collecting and smelting for precious metal content.

Geological facts

The reddish-brown color on the surface is likely 'gossan', which is iron oxide (rust) resulting from the oxidation of sulfide minerals like pyrite.

Field identification & locations

Look for heavy, metallic inclusions in quartz veins; often found in stream beds or near old mines. Use a streak test: pyrite has a greenish-black streak, while real gold has a golden-yellow streak.

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