Gold in Gossan (or Ironstone Matrix)
Native Gold in Goethite/Limonite matrix · Mineral Specimen / Precious Metal Ore
Crystal System
Cubic (Isometric) for Gold; Amorphous to Orthorhombic for matrix. Habit: granular, dendritic, or leaf gold in massive matrix.
Mineral Group
Native Elements (Gold) and Oxides/Hydroxides (Matrix)
Chemical Formula
Au (Native Element) on FeO(OH)·nH2O (Matrix)
Formation Process
Secondary enrichment or primary hydrothermal. The gold is often primary, while the dark matrix (Gossan) forms through the weathering of iron-rich sulfide minerals like pyrite.
About This Crystal
A heavy, rustic mineral specimen featuring a dark, iron-rich, earthy matrix (gossan) with visible metallic yellow gold inclusions. The gold appears as small, irregular grains or leaf-like flakes. The matrix is largely opaque with a dull to sub-metallic luster.
Physical Characteristics
Color: Yellow (Gold), Brown/Grey (Matrix); Streak: Yellow; Cleavage: None; Fracture: Uneven/Hackly; Specific Gravity: ~19.3 (Gold), ~3.3-4.3 (Matrix); Non-fluorescent.
Optical Properties
Opaque; Metallic luster on the gold grains; Dull to earthy luster on the matrix. No pleochroism or birefringence due to opacity.
Hardness & Durability
Origin Region
Notable sources include Western Australia, California (USA), or Witwatersrand (South Africa). Typically found in the oxidized zone of hydrothermal ore deposits.
Hardness & Durability
Mohs 2.5-3 (Gold), 5-5.5 (Matrix). Gold is highly malleable and ductile, while the matrix is brittle and can be crumbly.
Care & Maintenance
Clean with warm soapy water only; avoid harsh acids (though Gold is acid-resistant, the matrix is not). Store separately to prevent scratching the soft metal.
Rarity & Value
Rare. Value is determined by the weight of the gold content and the aesthetic appeal of the specimen. It is highly valued by collectors and as an investment.
Special Characteristics
Malleability (the gold can be dented by a pin without shattering); high density; distinct metallic luster that does not tarnish.
Lore & History
Gold has been the universal symbol of wealth, divinity, and the sun across almost every human culture. Historically used in coinage, jewelry, and alchemy. Metaphysically associated with the solar plexus chakra and abundance.