"Aluminium occurs widely on earth, and indeed is the third most abundant element in the Earth's crust (8.3%). Gallium is found in the earth with an abundance of 13 ppm. Indium is the 61st most abundant element in the earth's crust, and thallium is found in moderate amounts throughout the planet. Nihonium is never found in nature and therefore is termed a synthetic element. Several group 13 elements have biological roles in the ecosystem. Boron is a trace element in humans and is essential for some plants. Lack of boron can lead to stunted plant growth, while an excess can"
"elements in Earth's crust, having an average mass fraction of 0.001 ppm in crustal rock; platinum is 10 times more abundant, gold is 40 times more abundant, and silver and mercury are 80 times more abundant. Tellurium is about as abundant as iridium. In contrast to its low abundance in crustal rock, iridium is relatively common in meteorites, with concentrations of 0.5 ppm or more. The overall concentration of iridium on Earth is thought to be much higher than what is observed in crustal rocks, but because of the density and siderophilic (""iron-loving"") character of iridium, it descended below the"
"up approximately 2.6% of the Earth's crust measured by weight, making it the sixth most abundant element overall and the most abundant alkali metal. Potassium makes up approximately 1.5% of the Earth's crust and is the seventh most abundant element. Sodium is found in many different minerals, of which the most common is ordinary salt (sodium chloride), which occurs in vast quantities dissolved in seawater. Other solid deposits include halite, amphibole, cryolite, nitratine, and zeolite. Many of these solid deposits occur as a result of ancient seas evaporating, which still occurs now in places such as Utah's Great Salt Lake"
"Earth's crust, quartz (SiO) is the most abundant mineral species. It is characterized by its high chemical and physical resistivity. Quartz has several polymorphs, including tridymite and cristobalite at high temperatures, high-pressure coesite, and ultra-high pressure stishovite. The latter mineral can only be formed on Earth by meteorite impacts, and its structure has been composed so much that it had changed from a silicate structure to that of rutile (TiO). The silica polymorph that is most stable at the Earth's surface is α-quartz. Its counterpart, β-quartz, is present only at high temperatures and pressures (changes to α-quartz below 573 °C"
"represented by stars, planets and living beings. The balance is made of dark energy and dark matter, both of which are poorly understood at present. Hydrogen, carbon, nitrogen, and oxygen constitute the great bulk of the Earth's atmosphere, oceans, crust, and biosphere; the remaining nonmetals have abundances of 0.5 per cent or less. In comparison, 35 per cent of the crust is made up of the metals sodium, magnesium, aluminium, potassium and iron; together with a metalloid, silicon. All other metals and metalloids have abundances within the crust, oceans or biosphere of 0.2 per cent or less. Nonmetals, and metalloids,"
"earth's crust at a concentration of two to six parts per million (ppm), much of which is in soils, where it has a concentration of six ppm. Beryllium is one of the rarest elements in seawater, even rarer than elements such as scandium, with a concentration of 0.2 parts per trillion. However, in freshwater, beryllium is somewhat more common, with a concentration of 0.1 parts per billion. Magnesium and calcium are very common in the earth's crust, being respectively the fifth- eighth-most-abundant elements. None of the alkaline earth metals are found in their elemental state. Common magnesium--containing minerals are carnallite,"
"of uranium and thorium. Oxygen and silicon are notably the most common elements in the crust. On Earth and in rocky planets in general, silicon and oxygen are far more common than their cosmic abundance. The reason is that they combine with each other to form silicate minerals. In this way, they are the lightest of all of the two-percent ""astronomical metals"" (i.e., non-hydrogen and helium elements) to form a solid that is refractory to the Sun's heat, and thus cannot boil away into space. All elements lighter than oxygen have been removed from the crust in this way. ""Rare"""
"iron 5.6%, calcium 4.2%, sodium 2.5%, magnesium 2.4%, potassium 2.0%, and titanium 0.61%. Other elements occur at less than 0.15%. For a complete list, see abundance of elements in Earth's crust. The graph at right illustrates the relative atomic-abundance of the chemical elements in Earth's upper continental crust— the part that is relatively accessible for measurements and estimation. Many of the elements shown in the graph are classified into (partially overlapping) categories: Note that there are two breaks where the unstable (radioactive) elements technetium (atomic number 43) and promethium (atomic number 61) would be. These elements are surrounded by stable"
"titanium, zirconium and hafnium, the abundance decreases with increase of atomic mass. Titanium is the seventh most abundant metal in Earth's crust and has an abundance of 6320 ppm, while zirconium has an abundance of 162 ppm and hafnium has only an abundance of 3 ppm. All three stable elements occur in heavy mineral sands ore deposits, which are placer deposits formed, most usually in beach environments, by concentration due to the specific gravity of the mineral grains of erosion material from mafic and ultramafic rock. The titanium minerals are mostly anatase and rutile, and zirconium occurs in the mineral"
"the 19th century. Mercury is an extremely rare element in Earth's crust, having an average crustal abundance by mass of only 0.08 parts per million (ppm). Because it does not blend geochemically with those elements that constitute the majority of the crustal mass, mercury ores can be extraordinarily concentrated considering the element's abundance in ordinary rock. The richest mercury ores contain up to 2.5% mercury by mass, and even the leanest concentrated deposits are at least 0.1% mercury (12,000 times average crustal abundance). It is found either as a native metal (rare) or in cinnabar, metacinnabar, corderoite, livingstonite and other"
"Uranium is a naturally occurring element that can be found in low levels within all rock, soil, and water. Uranium is the 51st element in order of abundance in the Earth's crust. Uranium is also the highest-numbered element to be found naturally in significant quantities on Earth and is almost always found combined with other elements. The decay of uranium, thorium, and potassium-40 in the Earth's mantle is thought to be the main source of heat that keeps the outer core liquid and drives mantle convection, which in turn drives plate tectonics. Uranium's average concentration in the Earth's crust is"
"°C respectively are the second-highest among all the metalloids and nonmetals, being only surpassed by boron. Silicon is the eighth most common element in the universe by mass, but very rarely occurs as the pure element in the Earth's crust. It is most widely distributed in dusts, sands, planetoids, and planets as various forms of silicon dioxide (silica) or silicates. More than 90% of the Earth's crust is composed of silicate minerals, making silicon the second most abundant element in the Earth's crust (about 28% by mass) after oxygen. Most silicon is used commercially without being separated, and often with"
"since decayed and no longer contribute. In the Earth's crust, thorium is much more abundant: with an abundance of 8.1 parts per million (ppm), it is one of the most abundant of the heavy elements, almost as abundant as lead (13 ppm) and more abundant than tin (2.1 ppm). This is because thorium is likely to form oxide minerals that do not sink into the core; it is classified as a lithophile. Common thorium compounds are also poorly soluble in water. Thus, even though the Earth contains the same abundances of the elements as the Solar System as a whole,"
"an environment due to rapid leaching. Aluminum is the most common metal found in the Earth's crust. It is found in all soils and in all environments, from temperate to tropical. In a soluble state, it is highly toxic to plant life, as it inhibits root growth; however, in neutral and alkaline soils common to the temperate zones, it is insoluble and therefore inert. Soil fertility is directly influenced by how acidic it is, as the more acidic, the higher the level of aluminum toxicity; in areas where the pH drops below 5, aluminum becomes soluble and can enter into"
"was its ability to form compounds with hydrogen. Under these conditions, the s- and f-block metals were strongly enriched during the formation of the Earth. The most enriched elements are rubidium, strontium and barium, which between them account for over 50 percent by mass of all elements heavier than iron in the Earth's crust. The nonmetallic lithophiles – phosphorus and the halogens – exist on Earth as ionic salts with s-block metals in pegmatites and seawater. With the exception of fluorine, whose hydride forms hydrogen bonds and is therefore of relatively low volatility, these elements have had their concentrations on"
"Earth significantly reduced through escape of volatile hydrides during the Earth's formation. Although they are present in the Earth's crust in concentrations quite close to their solar abundances, phosphorus and the heavier halogens are probably significantly depleted ""on Earth as a whole"" relative to their solar abundances. Several transition metals, including chromium, molybdenum, iron and manganese, show ""both"" lithophile ""and"" siderophile characteristics and can be found in both these two layers. Although these metals form strong bonds with oxygen and are never found in the Earth's crust in the free state, metallic forms of these elements are thought very likely"
"point of nitrogen. Yttrium is found in most rare-earth minerals, it is found in some uranium ores, but is never found in the Earth's crust as a free element. About 31 ppm of the Earth's crust is yttrium, making it the 28th most abundant element, 400 times more common than silver. Yttrium is found in soil in concentrations between 10 and 150 ppm (dry weight average of 23 ppm) and in sea water at 9 ppt. Lunar rock samples collected during the American Apollo Project have a relatively high content of yttrium. Yttrium has no known biological role, though it"
"Earth as a whole (behind iron, oxygen and silicon), making up 13% of the planet's mass and a large fraction of planet's mantle. The relative abundance of magnesium is related to the fact that it is easily built up in supernova stars from a sequential addition of three helium nuclei to carbon (which in turn is made from three helium nuclei). Due to magnesium ion's high solubility in water, it is the third most abundant element dissolved in seawater. The free element (metal) is not found naturally on Earth, as it is highly reactive (though once produced, it is coated"
"of manganese are found in much the same sites as are those of aluminium and titanium, owing to manganese's great reactivity towards oxygen. Because they are so concentrated in the dense core, siderophile elements are known for their rarity in the Earth's crust. Most of them have always been known as precious metals because of this. Iridium is the rarest transition metal occurring within the Earth's crust, with an abundance by mass of less than one part per billion. Mineable deposits of precious metals usually form as a result of the erosion of ultramafic rocks, but are not highly concentrated"
"element estimated to average 3 parts per million in the Earth's crust. It is the 45th most abundant element and the 36th among the metals. Nevertheless, it is more abundant than such elements as antimony, cadmium, tin, and tungsten, and two orders of magnitude more abundant than mercury and silver; it is 3.3% as abundant as rubidium, with which it is closely associated, chemically. Due to its large ionic radius, caesium is one of the ""incompatible elements"". During magma crystallization, caesium is concentrated in the liquid phase and crystallizes last. Therefore, the largest deposits of caesium are zone pegmatite ore"
"aluminum. Although no chalcophile element is of high abundance in the Earth's crust, chalcophile elements constitute the bulk of commercially important metals. This is because, whereas lithophile elements require energy-intensive electrolysis for extraction, chalcophiles can be easily extracted by reduction with coke, and chalcophiles' geochemical concentration – which in extreme cases can exceed 100,000 times average crustal abundance. These greatest enrichments occur in high plateaux like the Tibetan Plateau and the Bolivian altiplano where large quantities of chalcophile elements have been uplifted through plate collisions. A side-effect of this in modern times is that the rarest chalcophiles (like mercury) are"
"metals below the crust are generally higher, with most being found in the largely iron-silicon-nickel core. Platinum, for example, comprises approximately 1 part per billion of the crust whereas its concentration in the core is thought to be nearly 6,000 times higher. Recent speculation suggests that uranium (and thorium) in the core may generate a substantial amount of the heat that drives plate tectonics and (ultimately) sustains the Earth's magnetic field. The winning of heavy metals from their ores is a complex function of ore type, the chemical properties of the metals involved, and the economics of various extraction methods."
"Family, Tribe, Genus, and Species. The abundance and diversity of minerals is controlled directly by their chemistry, in turn dependent on elemental abundances in the Earth. The majority of minerals observed are derived from the Earth's crust. Eight elements account for most of the key components of minerals, due to their abundance in the crust. These eight elements, summing to over 98% of the crust by weight, are, in order of decreasing abundance: oxygen, silicon, aluminium, iron, magnesium, calcium, sodium and potassium. Oxygen and silicon are by far the two most important – oxygen composes 47% of the crust by"
"earth elements is a historical misnomer. The persistence of the term reflects unfamiliarity rather than true rarity. The more abundant rare earth elements are similarly concentrated in the crust compared to commonplace industrial metals such as chromium, nickel, copper, zinc, molybdenum, tin, tungsten, or lead. The two least abundant rare earth elements (thulium and lutetium) are nearly 200 times more common than gold. However, in contrast to the ordinary base and precious metals, rare earth elements have very little tendency to become concentrated in exploitable ore deposits. Consequently, most of the world's supply of rare earth elements comes from only"
"100 times higher than in the Milky Way in general. Phosphorus has a concentration in the Earth's crust of about one gram per kilogram (compare copper at about 0.06 grams). It is not found free in nature, but is widely distributed in many minerals, usually as phosphates. Inorganic phosphate rock, which is partially made of apatite (a group of minerals being, generally, pentacalcium triorthophosphate fluoride (hydroxide)), is today the chief commercial source of this element. According to the US Geological Survey (USGS), about 50 percent of the global phosphorus reserves are in the Arab nations. Large deposits of apatite are"
"krypton-82. Rubidium is the twenty-third most abundant element in the Earth's crust, roughly as abundant as zinc and rather more common than copper. It occurs naturally in the minerals leucite, pollucite, carnallite, and zinnwaldite, which contain as much as 1% rubidium oxide. Lepidolite contains between 0.3% and 3.5% rubidium, and is the commercial source of the element. Some potassium minerals and potassium chlorides also contain the element in commercially significant quantities. Seawater contains an average of 125 µg/L of rubidium compared to the much higher value for potassium of 408 mg/L and the much lower value of 0.3 µg/L for"
"up 1.5 parts per million of the earth's crust, making it the 53rd most abundant element there. The soils contain 1 to 10 parts per million of arsenic, and seawater contains 1.6 parts per billion of arsenic. Arsenic makes up 100 parts per billion of a typical human by weight. Some arsenic exists in elemental form, but most arsenic is found in the arsenic minerals orpiment, realgar, arsenopyrite, and enargite. Antimony makes up 0.2 parts per million of the earth's crust, making it the 63rd most abundant element there. The soils contain 1 part per million of antimony on average,"
"magnesite, and dolomite. Common calcium-containing minerals are chalk, limestone, gypsum, and anhydrite. Strontium is the fifteenth-most-abundant element in the Earth's crust. The principal minerals are celestite and strontianite. Barium is slightly less common, much of it in the mineral barite. Radium, being a decay product of uranium, is found in all uranium-bearing ores. Due to its relatively short half-life, radium from the Earth's early history has decayed, and present-day samples have all come from the much slower decay of uranium. Most beryllium is extracted from beryllium hydroxide. One production method is sintering, done by mixing beryl, sodium fluorosilicate, and soda"
"found in elemental form or in the form of sulfide minerals, sulfate minerals, or sulfosalt minerals. Stars of at least 12 times the mass of the sun produce sulfur in their cores via nuclear fusion. Sulfur is the tenth most abundant element in the universe, making up 500 parts per million of the universe by weight. Selenium makes up 0.05 parts per million of the earth's crust by weight. This makes it the 67th most abundant element in the earth's crust. Selenium makes up on average 5 parts per million of the soils. Seawater contains around 200 parts per trillion"
"with slightly less metal than the chemical formula would show. For example, the mineral FeO (wüstite) is written as , where ""x"" is usually around 0.05. Oxygen is present in the atmosphere in trace quantities in the form of carbon dioxide (). The Earth's crustal rock is composed in large part of oxides of silicon (silica , as found in granite and quartz), aluminium (aluminium oxide , in bauxite and corundum), iron (iron(III) oxide , in hematite and rust), and calcium carbonate (in limestone). The rest of the Earth's crust is also made of oxygen compounds, in particular various complex"
"of elements heavier than helium in the interstellar medium. When gravitational attraction causes this matter to coalesce and collapse new stars and planets are formed. The Earth's crust is made of approximately 5% of heavy metals by weight, with iron comprising 95% of this quantity. Light metals (~20%) and nonmetals (~75%) make up the other 95% of the crust. Despite their overall scarcity, heavy metals can become concentrated in economically extractable quantities as a result of mountain building, erosion, or other geological processes. Heavy metals are primarily found as lithophiles (rock-loving) or chalcophiles (ore-loving). Lithophile heavy metals are mainly f-block"
"the magnesium is expelled into the interstellar medium where it may recycle into new star systems. Magnesium is the eighth most abundant element in the Earth's crust and the fourth most common element in the Earth (after iron, oxygen and silicon), making up 13% of the planet's mass and a large fraction of the planet's mantle. It is the third most abundant element dissolved in seawater, after sodium and chlorine. Magnesium occurs naturally only in combination with other elements, where it invariably has a +2 oxidation state. The free element (metal) can be produced artificially, and is highly reactive (though"
"in selective loss of the very lightest elements (hydrogen and helium) and also volatile neon, carbon (as hydrocarbons), nitrogen and sulfur, as a result of solar heating in the early formation of the solar system. Oxygen, the most abundant Earth element by mass, is retained on Earth by combination with silicon. Aluminum at 8% by mass is more common in the Earth's crust than in the universe and solar system, but the composition of the far more bulky mantle, which has magnesium and iron in place of aluminum (which occurs there only at 2% of mass) more closely mirrors the"