Native Gold

Native Gold


a mineral, the natural solid solution of silver (from trace amounts to 43 percent) in gold; impurities are common (from trace amounts to 0.9 percent) of copper, iron, and, less often, bismuth, mercury, platinum, manganese, and other metals. Varieties are known with an enhanced content of up to 20 percent copper (copper gold, cuproaurite), up to 4 percent bismuth (bismuth gold, bismuthaurite), platinoids (platinum and iridium gold, porpezite Au, Pd; rhodite Au, Rh), and natural amalgams (Au, Hg).

Native gold crystallizes in a cubic system as octahedra, rhombic dodecahedra, cubes, and crystals of more complex shape; often these crystals are deformed, much elongated, forming small “wires” and “fibers” orparallelly compressed octahedral planes. Dendritic shapes are characteristic of native gold, particularly if it is of poor quality. Widely distributed are filamentous and irregular clump-shaped, “hooked,” separations of native gold; their surfaces often hold the imprints of the crystals of other minerals, aggregates of which included accumulations of native gold. Etching reveals the crystalline-grain structure of the gold particles.

Native gold is bright yellow or, depending on the impurities, pale yellow, reddish, or greenish. It does not cleave. It is soft (it can be scratched by a needle); its hardness on the mineralogical scale is 2.5 and its density is 1,560–1,970 kg per cu m. Native gold is divided, according to the size of the particles, into finely-dispersed material (under 1–5 microns), dustlike (5–50 microns), fine (0.05–2 mm), and coarse (over 2 mm). Native gold accumulations of over 5 g, readily distinguished by their coarseness, are called nuggets. The biggest’ nuggets found have not been preserved; those found in Australia-the Holtermann (with rock residues, 285 kg) and the Welcome Stranger (71 kg)-were re melted. In the USSR the eastern (Urals, Lena) and other regions are rich innuggets (the largest nugget found in the Urals weighs 36.2 kg). Valuable nuggets are preserved by the respective state.

Native gold is the principal form in which gold occurs naturally; it is concentrated in hydrothermal deposits and unevenly distributed in fissured, veined quartz and sulfides (pyrites, arsenopyrites, pyrrhotite). It is finely dispersed in substantially sulfide ores. When the ore oxidizes at the earth’s surface, the fine native gold partially dissolves and is redeposited; in a number of cases it enriches the upper parts of the ore bodies. The processes of their destruction result in the liberation of particles of native gold and the accumulation of these particles in placers; moving in water currents along with other clastic material, the particles are rolled, rounded, deformed, and partly recrystallized. Electrochemical corrosion results in a thin shell of high-quality gold, which leads to a general increase in the native gold assay in placers.


Petrovskaia, N. V., and A. I. Fastalovich. “Morfologiia i struktura samorodnogo zolota.” In Materialy po mineralogii zolota. Moscow, 1952.
Nikolaeva, L. A. “Osobennosti samorodnogo zolota.” Tr. Tsentralnogo nauchno-issledovatel skogo gornorazvedochnogo in-ta, 1967, no. 76.
Petrovskaia, N. V. “O tipomorfizme samorodnogo zolota.” In Problemy geologii minerarnykh mestorozhdenii, petrologii i mineralogii, vol. 2. Moscow, 1969.


References in periodicals archive ?
Native gold and processed gold also topped the list of imported goods in H1 2015, recording Dh50.
Mineralization in this target area occurs in the form of native gold in quartz veins primarily within the stockwork zone around the main Josh Vein.
The mineralization in Hobbs Pipe is predominantly monzodiorite-hosted disseminated gold in arsenopyrite and pyrite, and also native gold in stockwork quartz veins.
Data from Colombia show copper contents in native gold at the trace level only (Uribe, in press), and native gold occurrences with copper levels above one per cent seem a rarity anywhere in the world (Hough et al.
Native gold and uraninite are generally identified at surface in limonitic fractures within metavolcanic host rocks.
KODIAK KOWBOY b c 14-4-2005 Vice Regent Northern Dancer Victoria Regina Deputy Minister Mint Copy Bunty's Flight Shakney Silver Deputy Mr Prospector Raise A Native Gold Digger Silver Valley Seven Valleys Road At Sea Proud Pied Posse (b 2000) Blushing Groom Red God Runaway Bride Rahy Glorious Song Halo Ballade Raska Roberto Hail To Reason Bramalea Borishka Queen Maud Nearctic Vent Neurf Mr Prospector Raise A Native Gold Digger Forty Niner File Tom Rolfe Continue Coronado's Quest Damascus Sword Dancer Kerala Laughing Look Laughter Kokadrie (ch 2000) Best Turn Bold Ruler Shenanigans Turn-to Sweet Clementine Cox's Ridge Our Martha Ballydonnell Corday West Turn Jacinto Bold Ruler Cascade Win Nona Constance Black On Trust Perception Bred by Hartwell Farm in Kentucky.
It is shown that gold deposits of the Cretaceous Volcanic Arc of Cuba largely consist of native gold, telluride and pyrite, where arsenopyrite is almost absent.
15 metre wide mineralized zone containing quartz, silicified andesite breccia, native gold and acanthite (silver sulfide mineral).
While Davies - 21 earlier this month - still lives at home with parents Paul and Sue at the detached family home on a smart Barry estate, Hackett resides in a sprawling mansion on his native Gold Coast.
12] Native gold in the form of nuggets is pictured here one one stamp, while native copper is shown on another.
Alluvial deposits of native gold found in or along streams were the principal sources of the metal for the ancient civilizations of the Middle East.

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