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Cartoon cross-section showing manto ore deposits (USGS) [1] A polymetallic replacement deposit, also known as carbonate replacement deposit or high-temperature carbonate-hosted Ag-Pb-Zn deposit, [2] is an orebody of metallic minerals formed by the replacement of sedimentary, usually carbonate rock, by metal-bearing solutions in the vicinity of igneous intrusions. [3]
16th century cupellation furnaces (per Agricola). Cupellation is a refining process in metallurgy in which ores or alloyed metals are treated under very high temperatures and subjected to controlled operations to separate noble metals, like gold and silver, from base metals, like lead, copper, zinc, arsenic, antimony, or bismuth, present in the ore.
Gold is currently considered the heaviest monoisotopic element. Bismuth formerly held that distinction until alpha-decay of the 209 Bi isotope was observed. All isotopes of gold are either radioactive or, in the case of 197 Au, observationally stable, meaning that 197 Au is predicted to be radioactive but no actual decay has been observed. [4]
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Gold is a soft metal (MH 2.5–3) [41] that is easily deformed. [42] ... Sr 31 Pb 20, La 5 Pb 3 N and Yb 3 Pb 20. [142] It has reasonable to good corrosion resistance ...
79 Au gold; use 4.81 nΩm 20.51 nΩm 22.14 nΩm 22.55 nΩm 22.71 nΩm 39.7 nΩm ... 82 Pb lead; use 49 nΩm 192 nΩm 208 nΩm 211 nΩm 213 nΩm 383 nΩm
N.B. Pilling and R.E. Bedworth [2] suggested in 1923 that metals can be classed into two categories: those that form protective oxides, and those that cannot. They ascribed the protectiveness of the oxide to the volume the oxide takes in comparison to the volume of the metal used to produce this oxide in a corrosion process in dry air.
The Goldschmidt classification, [1] [2] developed by Victor Goldschmidt (1888–1947), is a geochemical classification which groups the chemical elements within the Earth according to their preferred host phases into lithophile (rock-loving), siderophile (iron-loving), chalcophile (sulfide ore-loving or chalcogen-loving), and atmophile (gas-loving) or volatile (the element, or a compound in ...