Gold
Native Gold · Precious Metal / Mineral Specimen
Crystal System
Cubic (Isometric); habit is typically octahedral, dodecahedral, or cubic, but most commonly occurs as dendritic growths, grains, or irregular plates and masses.
Mineral Group
Native Elements
Chemical Formula
Au
Formation Process
Primary formation occurs via hydrothermal fluids at high temperatures in quartz veins within volcanic or metamorphic rocks. Secondary formation occurs through weathering and accumulation in sedimentary placer deposits.
About This Crystal
This specimen shows metallic, bright golden-yellow flakes and plates with a high luster, partially embedded in a dark, fine-grained host rock (likely basalt or shale). The gold displays a characteristic hackly fracture and lacks distinct crystal faces in this view, appearing more as a flattened leaf or coating.
Physical Characteristics
Color: Golden-yellow; Streak: Golden-yellow; Luster: Metallic; Cleavage: None; Fracture: Hackly; Specific Gravity: 19.3 (when pure); Tenacity: Highly malleable and ductile; Fluorescence: None.
Optical Properties
Opaque; high reflectivity; isotropic; no pleochroism or birefringence due to its metallic and cubic nature.
Hardness & Durability
Origin Region
Notable sources include the Witwatersrand (South Africa), California and Alaska (USA), Victoria (Australia), and the Yukon (Canada). It typically occurs in hydrothermal quartz veins or as secondary alluvial deposits.
Hardness & Durability
Mohs Hardness: 2.5–3.0. It is extremely soft and easily scratched or dented. It has high toughness due to malleability (it bends rather than breaks) but low wearability for unprotected jewelry.
Care & Maintenance
Clean with warm, soapy water and a soft cloth. Avoid harsh chemicals as they can affect the host rock. Store separately to prevent scratches from harder minerals. Gold does not tarnish or fade in sunlight.
Rarity & Value
Rare. Value is dictated by the current spot price of gold (per ounce), with significant premiums for aesthetic matrix specimens. Rarity is high for well-crystallized or large-native samples.
Special Characteristics
Extreme density (sectile properties) and remarkable malleability. It is one of the few elements found in its pure native state in nature.
Lore & History
Known since antiquity, gold was associated with the sun and royalty by the Egyptians and Aztecs. Historically used as a standard for currency and wealth. Symbolically, it is traditionally believed to represent purity, vitality, and the perfection of matter.