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Mineral symbols (text abbreviations) are used to abbreviate mineral groups, subgroups, and species, just as lettered symbols are used for the chemical elements. The first set of commonly used mineral symbols was published in 1983 and covered the common rock-forming minerals using 192 two- or three-lettered symbols. [ 1 ]
Iron ore (banded iron formation) Manganese ore – psilomelane (size: 6.7 × 5.8 × 5.1 cm) Lead ore – galena and anglesite (size: 4.8 × 4.0 × 3.0 cm). Ore is natural rock or sediment that contains one or more valuable minerals, typically including metals, concentrated above background levels, and that is economically viable to mine and process.
The name of the element is derived from the Greek word χρῶμα, chrōma, meaning color, [12] because many chromium compounds are intensely colored. Industrial production of chromium proceeds from chromite ore (mostly FeCr 2 O 4) to produce ferrochromium, an iron-chromium alloy, by means of aluminothermic or silicothermic reactions ...
When chromite ore is exposed to surface conditions, weathering and oxidation can occur. The element chromium is most abundant in chromite in the form of trivalent (Cr-III). When chromite ore is exposed to aboveground conditions, Cr-III can be converted to Cr-VI, which is the hexavalent state of chromium.
Chrome orange – chrome yellow and chrome red. Chrome red – basic lead chromate – PbCrO 4 +PbO; Chrome yellow/Paris yellow/Leipzig yello – lead chromate, PbCrO 4; Cinnabar/vermilion – refers to several substances, among them: mercury(II) sulfide (HgS), or native vermilion (the common ore of mercury). Copper Glance – copper(I) sulfide ...
Niobium is a chemical element; it has symbol Nb (formerly columbium, Cb) and atomic number 41. It is a light grey, crystalline, and ductile transition metal . Pure niobium has a Mohs hardness rating similar to pure titanium , [ 8 ] and it has similar ductility to iron .
Also acid ionization constant or acidity constant. A quantitative measure of the strength of an acid in solution expressed as an equilibrium constant for a chemical dissociation reaction in the context of acid-base reactions. It is often given as its base-10 cologarithm, p K a. acid–base extraction A chemical reaction in which chemical species are separated from other acids and bases. acid ...
The recovered ore also has drawbacks. The carbonate ore is more difficult to smelt than a haematite or other oxide ore. Driving off the carbonate as carbon dioxide requires more energy and so the ore 'kills' the blast furnace if added directly. Instead the ore must be given a preliminary roasting step.