Concept
Bauxite
Related concepts (20)
Ore
Ore is natural rock or sediment that contains one or more valuable minerals concentrated above background levels, typically containing metals, that can be mined, treated and sold at a profit. The grade of ore refers to the concentration of the desired material it contains. The value of the metals or minerals a rock contains must be weighed against the cost of extraction to determine whether it is of sufficiently high grade to be worth mining, and is therefore considered an ore.
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southern subregion of a single continent called America. South America is bordered on the west by the Pacific Ocean and on the north and east by the Atlantic Ocean; North America and the Caribbean Sea lie to the northwest.
China
China (), officially the People's Republic of China (PRC), is a country in East Asia. It is the world's second-most populous country with a population exceeding 1.4 billion. China spans the equivalent of five time zones and borders fourteen countries by land, tied with Russia as having the most of any country in the world. With an area of nearly , it is the world's third largest country by total land area. The country consists of 22 provinces, five autonomous regions, four municipalities, and two semi-autonomous special administrative regions.
Gold
Gold is a chemical element with the symbol Au () and atomic number 79. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile metal in pure form. Chemically, gold is a transition metal and a group 11 element. It is one of the least reactive chemical elements and is solid under standard conditions. Gold often occurs in free elemental (native state), as nuggets or grains, in rocks, veins, and alluvial deposits.
Calcium oxide
Calcium oxide (formula: CaO), commonly known as quicklime or burnt lime, is a widely used chemical compound. It is a white, caustic, alkaline, crystalline solid at room temperature. The broadly used term lime connotes calcium-containing inorganic compounds, in which carbonates, oxides, and hydroxides of calcium, silicon, magnesium, aluminium, and iron predominate. By contrast, quicklime specifically applies to the single compound calcium oxide. Calcium oxide that survives processing without reacting in building products, such as cement, is called free lime.
Mineral
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form. The geological definition of mineral normally excludes compounds that occur only in living organisms. However, some minerals are often biogenic (such as calcite) or organic compounds in the sense of chemistry (such as mellite). Moreover, living organisms often synthesize inorganic minerals (such as hydroxylapatite) that also occur in rocks.
Aluminium hydroxide
Aluminium hydroxide, , is found in nature as the mineral gibbsite (also known as hydrargillite) and its three much rarer polymorphs: bayerite, doyleite, and nordstrandite. Aluminium hydroxide is amphoteric, i.e., it has both basic and acidic properties. Closely related are aluminium oxide hydroxide, AlO(OH), and aluminium oxide or alumina (), the latter of which is also amphoteric. These compounds together are the major components of the aluminium ore bauxite. Aluminium hydroxide also forms a gelatinous precipitate in water.
Red mud
Red mud, now more frequently termed bauxite residue, is an industrial waste generated during the processing of bauxite into alumina using the Bayer process. It is composed of various oxide compounds, including the iron oxides which give its red colour. Over 95% of the alumina produced globally is through the Bayer process; for every tonne of alumina produced, approximately 1 to 1.5 tonnes of red mud are also produced. Annual production of alumina in 2020 was over 133 million tonnes resulting in the generation of over 175 million tonnes of red mud.
Corundum
Corundum is a crystalline form of aluminium oxide () typically containing traces of iron, titanium, vanadium and chromium. It is a rock-forming mineral. It is a naturally transparent material, but can have different colors depending on the presence of transition metal impurities in its crystalline structure. Corundum has two primary gem varieties: ruby and sapphire. Rubies are red due to the presence of chromium, and sapphires exhibit a range of colors depending on what transition metal is present.
Laterite
Laterite is both a soil and a rock type rich in iron and aluminium and is commonly considered to have formed in hot and wet tropical areas. Nearly all laterites are of rusty-red coloration, because of high iron oxide content. They develop by intensive and prolonged weathering of the underlying parent rock, usually when there are conditions of high temperatures and heavy rainfall with alternate wet and dry periods. Tropical weathering (laterization) is a prolonged process of chemical weathering which produces a wide variety in the thickness, grade, chemistry and ore mineralogy of the resulting soils.