Rock Identifier
Gold bullion bars (Native gold (Au), likely cast or refined metal) — mineral
mineral

Gold bullion bars

Native gold (Au), likely cast or refined metal

AI-generated identification · may be incorrect

Metallic yellow-gold color, very high luster, malleable and exceptionally dense; Mohs hardness about 2.5–3, cubic crystal system in natural form, with indistinct cleavage. The scale shows approximately 103.79 g for one bar, though the visible specimens may be gold-bearing alloy or plated metal.

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Physical properties

Metallic yellow-gold color, very high luster, malleable and exceptionally dense; Mohs hardness about 2.5–3, cubic crystal system in natural form, with indistinct cleavage. The scale shows approximately 103.79 g for one bar, though the visible specimens may be gold-bearing alloy or plated metal.

Formation & geological history

Native gold forms hydrothermally in quartz veins and alluvial deposits through geological processes spanning many ages; these bars are human-processed by melting and casting rather than natural rock formation.

Uses & applications

Used as bullion, investment, jewelry, electronics, and monetary reserves. Collector value depends mainly on verified purity, weight, hallmark, and provenance.

Geological facts

Gold’s density is about 19.3 g/cm³, allowing genuine bars to feel unusually heavy for their size. Handwritten markings are not proof of authenticity; assay testing is essential.

Field identification & locations

The image shows metallic cast bars, not a conventional rock specimen. Confirm identity with a fineness hallmark, precise density or specific-gravity test, magnet test, XRF assay, and professional verification; common sources include mined gold refined at bullion facilities.