Portal:Minerals
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The Minerals Portal
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.
The concept of mineral is distinct from rock, which is any bulk solid geologic material that is relatively homogeneous at a large enough scale. A rock may consist of one type of mineral or may be an aggregate of two or more different types of minerals, spacially segregated into distinct phases.
Some natural solid substances without a definite crystalline structure, such as opal or obsidian, are more properly called mineraloids. If a chemical compound occurs naturally with different crystal structures, each structure is considered a different mineral species. Thus, for example, quartz and stishovite are two different minerals consisting of the same compound, silicon dioxide. (Full article...)
Mineralogy is a subject of geology specializing in the scientific study of the chemistry, crystal structure, and physical (including optical) properties of minerals and mineralized artifacts. Specific studies within mineralogy include the processes of mineral origin and formation, classification of minerals, their geographical distribution, as well as their utilization. (Full article...)
Selected articles
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Cinnabar (/ˈsɪnəˌbɑːr/; from Ancient Greek κιννάβαρι (kinnábari)), or cinnabarite (/ˌsɪnəˈbɑːraɪt/), also known as mercurblende is the bright scarlet to brick-red form of mercury(II) sulfide (HgS). It is the most common source ore for refining elemental mercury and is the historic source for the brilliant red or scarlet pigment termed vermilion and associated red mercury pigments.
Cinnabar generally occurs as a vein-filling mineral associated with volcanic activity and alkaline hot springs. The mineral resembles quartz in symmetry and it exhibits birefringence. Cinnabar has a mean refractive index near 3.2, a hardness between 2.0 and 2.5, and a specific gravity of approximately 8.1. The color and properties derive from a structure that is a hexagonal crystalline lattice belonging to the trigonal crystal system, crystals that sometimes exhibit twinning.
Cinnabar has been used for its color since antiquity in the Near East, including as a rouge-type cosmetic, in the New World since the Olmec culture, and in China since as early as the Yangshao culture, where it was used in coloring stoneware.
Associated modern precautions for the use and handling of cinnabar arise from the toxicity of the mercury component, which was recognized as early as ancient Rome. (Full article...) -
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Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Another solid form of carbon known as graphite is the chemically stable form of carbon at room temperature and pressure, but diamond is metastable and converts to it at a negligible rate under those conditions. Diamond has the highest hardness and thermal conductivity of any natural material, properties that are used in major industrial applications such as cutting and polishing tools. They are also the reason that diamond anvil cells can subject materials to pressures found deep in the Earth.
Because the arrangement of atoms in diamond is extremely rigid, few types of impurity can contaminate it (two exceptions are boron and nitrogen). Small numbers of defects or impurities (about one per million of lattice atoms) can color a diamond blue (boron), yellow (nitrogen), brown (defects), green (radiation exposure), purple, pink, orange, or red. Diamond also has a very high refractive index and a relatively high optical dispersion.
Most natural diamonds have ages between 1 billion and 3.5 billion years. Most were formed at depths between 150 and 250 kilometres (93 and 155 mi) in the Earth's mantle, although a few have come from as deep as 800 kilometres (500 mi). Under high pressure and temperature, carbon-containing fluids dissolved various minerals and replaced them with diamonds. Much more recently (hundreds to tens of million years ago), they were carried to the surface in volcanic eruptions and deposited in igneous rocks known as kimberlites and lamproites.
Synthetic diamonds can be grown from high-purity carbon under high pressures and temperatures or from hydrocarbon gases by chemical vapor deposition (CVD). Imitation diamonds can also be made out of materials such as cubic zirconia and silicon carbide. Natural, synthetic, and imitation diamonds are most commonly distinguished using optical techniques or thermal conductivity measurements. (Full article...) -
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In crystallography, crystal structure is a description of the ordered arrangement of atoms, ions, or molecules in a crystalline material. Ordered structures occur from the intrinsic nature of the constituent particles to form symmetric patterns that repeat along the principal directions of three-dimensional space in matter.
The smallest group of particles in the material that constitutes this repeating pattern is the unit cell of the structure. The unit cell completely reflects the symmetry and structure of the entire crystal, which is built up by repetitive translation of the unit cell along its principal axes. The translation vectors define the nodes of the Bravais lattice.
The lengths of the principal axes, or edges, of the unit cell and the angles between them are the lattice constants, also called lattice parameters or cell parameters. The symmetry properties of the crystal are described by the concept of space groups. All possible symmetric arrangements of particles in three-dimensional space may be described by the 230 space groups.
The crystal structure and symmetry play a critical role in determining many physical properties, such as cleavage, electronic band structure, and optical transparency. (Full article...) -
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Magnetite is a mineral and one of the main iron ores, with the chemical formula Fe2+Fe3+2O4. It is one of the oxides of iron, and is ferrimagnetic; it is attracted to a magnet and can be magnetized to become a permanent magnet itself. With the exception of extremely rare native iron deposits, it is the most magnetic of all the naturally occurring minerals on Earth. Naturally magnetized pieces of magnetite, called lodestone, will attract small pieces of iron, which is how ancient peoples first discovered the property of magnetism.
Magnetite is black or brownish-black with a metallic luster, has a Mohs hardness of 5–6 and leaves a black streak. Small grains of magnetite are very common in igneous and metamorphic rocks.
The chemical IUPAC name is iron(II,III) oxide and the common chemical name is ferrous-ferric oxide. (Full article...) -
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Tourmaline (/ˈtʊərməlɪn, -ˌliːn/ TOOR-mə-lin, -leen) is a crystalline silicate mineral group in which boron is compounded with elements such as aluminium, iron, magnesium, sodium, lithium, or potassium. This gemstone comes in a wide variety of colors.
The name is derived from the Sinhalese tōramalli (ටෝරමල්ලි), which refers to the carnelian gemstones. (Full article...) -
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In crystallography, the cubic (or isometric) crystal system is a crystal system where the unit cell is in the shape of a cube. This is one of the most common and simplest shapes found in crystals and minerals.
There are three main varieties of these crystals:- Primitive cubic (abbreviated cP and alternatively called simple cubic)
- Body-centered cubic (abbreviated cI or bcc)
- Face-centered cubic (abbreviated cF or fcc)
Note: the term fcc is often used in synonym for the cubic close-packed or ccp structure occurring in metals. However, fcc stands for a face-centered-cubic Bravais lattice, which is not necessarily close-packed when a motif is set onto the lattice points. E.g. the diamond and the zincblende lattices are fcc but not close-packed.
Each is subdivided into other variants listed below. Although the unit cells in these crystals are conventionally taken to be cubes, the primitive unit cells often are not. (Full article...) -
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Corundum is a crystalline form of aluminium oxide (Al2O3) 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. A rare type of sapphire, padparadscha sapphire, is pink-orange.
The name "corundum" is derived from the Tamil-Dravidian word kurundam (ruby-sapphire) (appearing in Sanskrit as kuruvinda).
Because of corundum's hardness (pure corundum is defined to have 9.0 on the Mohs scale), it can scratch almost all other minerals. It is commonly used as an abrasive on sandpaper and on large tools used in machining metals, plastics, and wood. Emery, a variety of corundum with no value as a gemstone, is commonly used as an abrasive. It is a black granular form of corundum, in which the mineral is intimately mixed with magnetite, hematite, or hercynite.
In addition to its hardness, corundum has a density of 4.02 g/cm3 (251 lb/cu ft), which is unusually high for a transparent mineral composed of the low-atomic mass elements aluminium and oxygen. (Full article...) -
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In crystallography, a crystal system is a set of point groups (a group of geometric symmetries with at least one fixed point). A lattice system is a set of Bravais lattices. Space groups are classified into crystal systems according to their point groups, and into lattice systems according to their Bravais lattices. Crystal systems that have space groups assigned to a common lattice system are combined into a crystal family.
The seven crystal systems are triclinic, monoclinic, orthorhombic, tetragonal, trigonal, hexagonal, and cubic. Informally, two crystals are in the same crystal system if they have similar symmetries (though there are many exceptions). (Full article...) -
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Turquoise is an opaque, blue-to-green mineral that is a hydrous phosphate of copper and aluminium, with the chemical formula CuAl6(PO4)4(OH)8·4H2O. It is rare and valuable in finer grades and has been prized as a gemstone for millennia due to its hue.
Like most other opaque gems, turquoise has been devalued by the introduction of treatments, imitations, and synthetics into the market. The robin egg blue or sky blue color of the Persian turquoise mined near the modern city of Nishapur, Iran, has been used as a guiding reference for evaluating turquoise quality. (Full article...) -
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Zircon (/ˈzɜːrkɒn, -kən/) is a mineral belonging to the group of nesosilicates and is a source of the metal zirconium. Its chemical name is zirconium(IV) silicate, and its corresponding chemical formula is ZrSiO4. An empirical formula showing some of the range of substitution in zircon is (Zr1–y, REEy)(SiO4)1–x(OH)4x–y. Zircon precipitates from silicate melts and has relatively high concentrations of high field strength incompatible elements. For example, hafnium is almost always present in quantities ranging from 1 to 4%. The crystal structure of zircon is tetragonal crystal system. The natural color of zircon varies between colorless, yellow-golden, red, brown, blue, and green.
The name derives from the Persian zargun, meaning "gold-hued". This word is changed into "jargoon", a term applied to light-colored zircons. The English word "zircon" is derived from Zirkon, which is the German adaptation of this word. Yellow, orange, and red zircon is also known as "hyacinth", from the flower hyacinthus, whose name is of Ancient Greek origin. (Full article...) -
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The mineral pyrite (/ˈpaɪraɪt/ PY-ryte), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula FeS2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral.
Pyrite's metallic luster and pale brass-yellow hue give it a superficial resemblance to gold, hence the well-known nickname of fool's gold. The color has also led to the nicknames brass, brazzle, and brazil, primarily used to refer to pyrite found in coal.
The name pyrite is derived from the Greek πυρίτης λίθος (pyritēs lithos), 'stone or mineral which strikes fire', in turn from πῦρ (pŷr), 'fire'. In ancient Roman times, this name was applied to several types of stone that would create sparks when struck against steel; Pliny the Elder described one of them as being brassy, almost certainly a reference to what is now called pyrite.
By Georgius Agricola's time, c. 1550, the term had become a generic term for all of the sulfide minerals. (Full article...) -
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Cleavage, in mineralogy and materials science, is the tendency of crystalline materials to split along definite crystallographic structural planes. These planes of relative weakness are a result of the regular locations of atoms and ions in the crystal, which create smooth repeating surfaces that are visible both in the microscope and to the naked eye. If bonds in certain directions are weaker than others, the crystal will tend to split along the weakly bonded planes. These flat breaks are termed "cleavage". The classic example of cleavage is mica, which cleaves in a single direction along the basal pinacoid, making the layers seem like pages in a book. In fact, mineralogists often refer to "books of mica".
Diamond and graphite provide examples of cleavage. Each is composed solely of a single element, carbon. In diamond, each carbon atom is bonded to four others in a tetrahedral pattern with short covalent bonds. The planes of weakness (cleavage planes) in a diamond are in four directions, following the faces of the octahedron. In graphite, carbon atoms are contained in layers in a hexagonal pattern where the covalent bonds are shorter (and thus even stronger) than those of diamond. However, each layer is connected to the other with a longer and much weaker van der Waals bond. This gives graphite a single direction of cleavage, parallel to the basal pinacoid. So weak is this bond that it is broken with little force, giving graphite a slippery feel as layers shear apart. As a result, graphite makes an excellent dry lubricant.
While all single crystals will show some tendency to split along atomic planes in their crystal structure, if the differences between one direction or another are not large enough, the mineral will not display cleavage. Corundum, for example, displays no cleavage. (Full article...) -
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Amethyst is a violet variety of quartz. The name comes from the Koine Greek αμέθυστος amethystos from α- a-, "not" and μεθύσκω (Ancient Greek) methysko / μεθώ metho (Modern Greek), "intoxicate", a reference to the belief that the stone protected its owner from drunkenness. Ancient Greeks wore amethyst and carved drinking vessels from it in the belief that it would prevent intoxification.
Amethyst, a semiprecious stone, is often used in jewelry. (Full article...) -
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Andesite (/ˈændəzaɪt/) is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predominantly of sodium-rich plagioclase plus pyroxene or hornblende.
Andesite is the extrusive equivalent of plutonic diorite. Characteristic of subduction zones, andesite represents the dominant rock type in island arcs. The average composition of the continental crust is andesitic. Along with basalts, andesites are a component of the Martian crust.
The name andesite is derived from the Andes mountain range, where this rock type is found in abundance. It was first applied by Christian Leopold von Buch in 1826. (Full article...) -
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Ruby is a pinkish red to blood-red colored gemstone, a variety of the mineral corundum (aluminium oxide). Ruby is one of the most popular traditional jewelry gems and is very durable. Other varieties of gem-quality corundum are called sapphires. Ruby is one of the traditional cardinal gems, alongside amethyst, sapphire, emerald, and diamond. The word ruby comes from ruber, Latin for red. The color of a ruby is due to the element chromium.
Some gemstones that are popularly or historically called rubies, such as the Black Prince's Ruby in the British Imperial State Crown, are actually spinels. These were once known as "Balas rubies".
The quality of a ruby is determined by its color, cut, and clarity, which, along with carat weight, affect its value. The brightest and most valuable shade of red, called blood-red or pigeon blood, commands a large premium over other rubies of similar quality. After color follows clarity: similar to diamonds, a clear stone will command a premium, but a ruby without any needle-like rutile inclusions may indicate that the stone has been treated. Ruby is the traditional birthstone for July and is usually pinker than garnet, although some rhodolite garnets have a similar pinkish hue to most rubies. The world's most valuable ruby to be sold at auction is the Sunrise Ruby. (Full article...) -
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Beryl (/ˈbɛrəl/ BERR-əl) is a mineral composed of beryllium aluminium silicate with the chemical formula Be3Al2Si6O18. Well-known varieties of beryl include emerald and aquamarine. Naturally occurring hexagonal crystals of beryl can be up to several meters in size, but terminated crystals are relatively rare. Pure beryl is colorless, but it is frequently tinted by impurities; possible colors are green, blue, yellow, pink, and red (the rarest). It is an ore source of beryllium. (Full article...) -
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Kaolinite (/ˈkeɪ.ələˌnaɪt, -lɪ-/ KAY-ə-lə-nyte, -lih-; also called kaolin) is a clay mineral, with the chemical composition: Al2Si2O5(OH)4. It is a layered silicate mineral, with one tetrahedral sheet of silica (SiO4) linked through oxygen atoms to one octahedral sheet of alumina (AlO6).
Kaolinite is a soft, earthy, usually white, mineral (dioctahedral phyllosilicate clay), produced by the chemical weathering of aluminium silicate minerals like feldspar. It has a low shrink–swell capacity and a low cation-exchange capacity (1–15 meq/100 g).
Rocks that are rich in kaolinite, and halloysite, are known as kaolin (/ˈkeɪ.əlɪn/) or china clay. In many parts of the world kaolin is colored pink-orange-red by iron oxide, giving it a distinct rust hue. Lower concentrations of iron oxide yield the white, yellow, or light orange colors of kaolin. Alternating lighter and darker layers are sometimes found, as at Providence Canyon State Park in Georgia, United States.
Kaolin is an important raw material in many industries and applications. Commercial grades of kaolin are supplied and transported as powder, lumps, semi-dried noodle or slurry. Global production of kaolin in 2021 was estimated to be 45 million tonnes, with a total market value of $US4.24 billion. (Full article...) -
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Borax (also referred to as sodium borate, tincal (/ˈtɪŋkəl/) and tincar (/ˈtɪŋkər/)) is a salt (ionic compound), a hydrated or anhydrous borate of sodium, with the chemical formula Na2H20B4O17 (also written as Na2B4O7·10H2O).
It is a colorless crystalline solid that dissolves in water to make a basic solution.
It is commonly available in powder or granular form and has many industrial and household uses, including as a pesticide, as a metal soldering flux, as a component of glass, enamel, and pottery glazes, for tanning of skins and hides, for artificial aging of wood, as a preservative against wood fungus, and as a pharmaceutic alkalizer. In chemical laboratories, it is used as a buffering agent.
The terms tincal and tincar refer to native borax, historically mined from dry lake beds in various parts of Asia. (Full article...) -
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Asbestos (/æsˈbɛstəs, æz-, -tɒs/ ass-BES-təs, az-, -toss) is a naturally occurring fibrous silicate mineral. There are six types, all of which are composed of long and thin fibrous crystals, each fibre (particulate with length substantially greater than width) being composed of many microscopic "fibrils" that can be released into the atmosphere by abrasion and other processes. Inhalation of asbestos fibres can lead to various dangerous lung conditions, including mesothelioma, asbestosis, and lung cancer. As a result of these health effects, asbestos is considered a serious health and safety hazard.
Archaeological studies have found evidence of asbestos being used as far back as the Stone Age to strengthen ceramic pots, but large-scale mining began at the end of the 19th century when manufacturers and builders began using asbestos for its desirable physical properties. Asbestos is an excellent thermal and electrical insulator, and is highly fire resistant, so for much of the 20th century, it was very commonly used across the world as a building material (particularly for its fire-retardant properties), until its adverse effects on human health were more widely recognized and acknowledged in the 1970s. Many buildings constructed before the 1980s contain asbestos.
The use of asbestos for construction and fireproofing has been made illegal in many countries. Despite this, at least 100,000 people are thought to die each year from diseases related to asbestos exposure.[citation needed] In part, this is because many older buildings still contain asbestos; in addition, the consequences of exposure can take decades to arise. The latency period (from exposure to the diagnosis of negative health effects) is typically 20 years. The most common diseases associated with chronic asbestos exposure are asbestosis (scarring of the lungs due to asbestos inhalation) and mesothelioma (a type of cancer).
Many developing countries still support the use of asbestos as a building material, and mining of asbestos is ongoing, with the top producer, Russia, having an estimated production of 790,000 tonnes in 2020. (Full article...) -
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Garnets ( /ˈɡɑːrnɪt/) are a group of silicate minerals that have been used since the Bronze Age as gemstones and abrasives.
All species of garnets possess similar physical properties and crystal forms, but differ in chemical composition. The different species are pyrope, almandine, spessartine, grossular (varieties of which are hessonite or cinnamon-stone and tsavorite), uvarovite and andradite. The garnets make up two solid solution series: pyrope-almandine-spessartine (pyralspite), with the composition range [Mg,Fe,Mn]3Al2(SiO4)3; and uvarovite-grossular-andradite (ugrandite), with the composition range Ca3[Cr,Al,Fe]2(SiO4)3. (Full article...) -
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Malachite is a copper carbonate hydroxide mineral, with the formula Cu2CO3(OH)2. This opaque, green-banded mineral crystallizes in the monoclinic crystal system, and most often forms botryoidal, fibrous, or stalagmitic masses, in fractures and deep, underground spaces, where the water table and hydrothermal fluids provide the means for chemical precipitation. Individual crystals are rare, but occur as slender to acicular prisms. Pseudomorphs after more tabular or blocky azurite crystals also occur. (Full article...) -
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Crystallography is the branch of science devoted to the study of molecular and crystalline structure and properties. The word crystallography is derived from the Ancient Greek word κρύσταλλος (krústallos; "clear ice, rock-crystal"), and γράφειν (gráphein; "to write"). In July 2012, the United Nations recognised the importance of the science of crystallography by proclaiming 2014 the International Year of Crystallography.
Crystallography is a broad topic, and there are many subareas such as X-ray crystallography which are themselves large scientific topics. It spans science ranging from the fundamentals of crystal structure to the mathematics of crystal geometry including those which are not periodic or quasicrystals. At the atomic scale it can involve the use of X-ray diffraction to produce experimental data which the tools of X-ray crystallography can convert into detailed positions of atoms and sometimes electron density. At the larger scale it includes experimental tools such as orientational imaging to examine the relative orientations at the grain boundary in materials. Crystallography plays a key role in many areas of established biology, chemistry and physics as well new developments in these fields. (Full article...) -
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Dolomite (/ˈdɒl.əˌmaɪt, ˈdoʊ.lə-/) is an anhydrous carbonate mineral composed of calcium magnesium carbonate, ideally CaMg(CO3)2. The term is also used for a sedimentary carbonate rock composed mostly of the mineral dolomite (see Dolomite (rock)). An alternative name sometimes used for the dolomitic rock type is dolostone. (Full article...) -
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Micas (/ˈmaɪkəz/ MY-kəz) are a group of silicate minerals whose outstanding physical characteristic is that individual mica crystals can easily be split into extremely thin elastic plates. This characteristic is described as perfect basal cleavage. Mica is common in igneous and metamorphic rock and is occasionally found as small flakes in sedimentary rock. It is particularly prominent in many granites, pegmatites, and schists, and "books" (large individual crystals) of mica several feet across have been found in some pegmatites.
Micas are used in products such as drywalls, paints, fillers, especially in parts for automobiles, roofing and shingles, as well as in electronics. The mineral is used in cosmetics and food to add "shimmer" or "frost." (Full article...) -
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Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO2. Quartz is, therefore, classified structurally as a framework silicate mineral and compositionally as an oxide mineral. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar.
Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral. The transformation from α-quartz to β-quartz takes place abruptly at 573 °C (846 K; 1,063 °F). Since the transformation is accompanied by a significant change in volume, it can easily induce microfracturing of ceramics or rocks passing through this temperature threshold.
There are many different varieties of quartz, several of which are classified as gemstones. Since antiquity, varieties of quartz have been the most commonly used minerals in the making of jewelry and hardstone carvings, especially in Europe and Asia.
Quartz is the mineral defining the value of 7 on the Mohs scale of hardness, a qualitative scratch method for determining the hardness of a material to abrasion. (Full article...)
Selected mineralogist
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Shen Kuo (Chinese: 沈括; 1031–1095) or Shen Gua, courtesy name Cunzhong (存中) and pseudonym Mengqi (now usually given as Mengxi) Weng (夢溪翁), was a Chinese polymath, scientist, and statesman of the Song dynasty (960–1279). Shen was a master in many fields of study including mathematics, optics, and horology. In his career as a civil servant, he became a finance minister, governmental state inspector, head official for the Bureau of Astronomy in the Song court, Assistant Minister of Imperial Hospitality, and also served as an academic chancellor. At court his political allegiance was to the Reformist faction known as the New Policies Group, headed by Chancellor Wang Anshi (1021–1085).
In his Dream Pool Essays or Dream Torrent Essays (夢溪筆談; Mengxi Bitan) of 1088, Shen was the first to describe the magnetic needle compass, which would be used for navigation (first described in Europe by Alexander Neckam in 1187). Shen discovered the concept of true north in terms of magnetic declination towards the north pole, with experimentation of suspended magnetic needles and "the improved meridian determined by Shen's [astronomical] measurement of the distance between the pole star and true north". This was the decisive step in human history to make compasses more useful for navigation, and may have been a concept unknown in Europe for another four hundred years (evidence of German sundials made circa 1450 show markings similar to Chinese geomancers' compasses in regard to declination). (Full article...) -
Image 2Adolf Knop (12 January 1828, in Altenau – 27 December 1893, in Karlsruhe) was a German geologist and mineralogist.
He studied mathematics and sciences at the University of Göttingen, where he was a pupil of chemist Friedrich Wohler and mineralogist Johann Friedrich Ludwig Hausmann. From 1849 he taught classes at the vocational school in Chemnitz. In 1857 he became an associate professor of geology and mineralogy at the University of Giessen, where in 1863 he attained a full professorship. In 1866 he relocated to Karlsruhe as a professor at the Polytechnic school. In 1878 he succeeded Moritz August Seubert as manager of the Grand Ducal Natural History Cabinet. (Full article...) -
Image 3Hans Peter Eugster (November 19, 1925, in Igis, Switzerland – December 17, 1987, in Baltimore, US) was a Swiss-American geochemist, mineralogist, and petrologist. (Full article...)
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Hanns Bruno Geinitz (16 October 1814 – 28 January 1900) was a German geologist, born at Altenburg, the capital of Saxe-Altenburg. (Full article...) -
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James De Carle Sowerby (5 June 1787 – 26 August 1871) was a British mineralogist, botanist, and illustrator. He received an education in chemistry.
Sowerby was born in London, the son of botanical artist James Sowerby (1757–1822), and his wife, Anne de Carle (1764–1815). He continued his father's work and published, together with his brother George Brettingham Sowerby I, the latter volumes of the Mineral Conchology of Great Britain, begun by their father. (Full article...) -
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Karl August Lossen (born Kreuznach (Rhineland), 5 January 1841; died Berlin, 24 February 1893) was a German petrologist and geologist.
After finishing his studies at the gymnasium of Kreuznach in 1859 Lossen became a mining engineer; he began by two and a half years of practical work, then studied at the Universities of Berlin and Halle, where he graduated in 1866; in the same year he became assistant geologist of the Prussian national geological survey. He began immediately his well-known petrolographic studies of the Harz Mountains, which lasted till his death. In 1870 he became instructor in petrology at the Berlin mining academy, and at the same time lecturer at the university. In 1873, he was made a member of the newly founded Prussian National Geological Institute, and in 1882 received the title of professor; he was a fellow of the Görres Society from its foundation. In 1886, he became an associate professor in the university. (Full article...) -
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Emil Wilhelm Cohen (12 October 1842 – 13 April 1905) was a German mineralogist and petrographer, born in Jutland. (Full article...) -
Image 8Ralph Early Grim (February 25, 1902 – August 19, 1989) was an American geologist and scientist, often referred to as the "Father of Mineralogy" because he made many discoveries during his investigations of clay materials. He was one of the most outstanding mineralogists of his time and was well-known throughout the world in the field of clay science and technology. Grim's career spanned over 60 years and he received many honors and awards in the field of mineralogy. Some of the textbooks he wrote have been standard university textbooks in mineralogy for many years. (Full article...)
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Alice Mary Dowse Weeks (August 26, 1909 – August 29, 1988) was an American geologist. Weeksite is named after her. She identified uranophane in 1953 along with Mary E. Thompson. Weeks was the first to propose the concept of oxidation of ore deposits that contain uranium, vanadium, and other accessory metals. She founded the Geology Department at Temple University in Philadelphia, and was a strong proponent of women in geology. (Full article...) -
Image 10Carlo Perrier (born July 7, 1886, in Turin, † May 22, 1948 in Genoa ) was an Italian mineralogist and chemist who did extensive research on the element technetium. With the discovery of technetium in 1937, he and Emilio Segrè accounted for the last gap in the periodic table. Technetium was the first element produced artificially (hence the name that Segrè and Perrier gave it).
His parents were named Bertolini. Perrier studied chemistry at the Polytechnic in Turin with a Laureate degree in 1908. From 1911 to 1912 he worked at the Laboratory for Physical Chemistry and Electrochemistry at ETH Zurich with Baur and Treadwell. He then worked as an assistant of Arnaldo Piutti at the University of Naples. There he made friends with Ferruccio Zambonini and involved with mineralogy and the study of radioactivity. He was Zambonini's assistant in Turin and, after a competition, became director of the State Geochemical Laboratory in Rome in 1921. In 1927 he completed his habilitation and after another competition became an associate professor in Messina. In 1929 he relocated to Palermo and in 1939 to the University of Genoa. (Full article...) -
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Albrecht Schrauf (14 December 1837, Vienna – 29 November 1897, Vienna) was an Austrian mineralogist and crystallographer. (Full article...) -
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Ignaz Edler von Born, also known as Ignatius von Born (Hungarian: Born Ignác, Romanian: Ignațiu von Born, Czech: Ignác Born) (26 December 1742 in Alba Iulia, Grand Principality of Transylvania, Habsburg monarchy – 24 July 1791 in Vienna), was a mineralogist and metallurgist. He was a prominent freemason, being head of Vienna's lodge and an influential anti-clerical writer. He was the leading scientist in the Holy Roman Empire during the 1770s in the Age of Enlightenment.
His interests include mining, mineralogy, palaeontology, chemistry, metallurgy and malacology. (Full article...) -
Image 13Jacques-Louis, Comte de Bournon FRS, FGS (21 January 1751 – 24 August 1825) was a French soldier and mineralogist who came to England after the French Revolution. He gained prominence in the scientific community, being elected a fellow of the Royal Society and was a founding member of the Geological Society before returning to France after the Bourbon Restoration. (Full article...)
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Lars Fredrik Svanberg (13 May 1805 – 16 July 1878) was a Swedish chemist and mineralogist. (Full article...) -
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Theodor Liebisch (29 April 1852, Breslau – 9 February 1922, Berlin) was a German mineralogist and crystallographer. (Full article...) -
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John Mawe (1764 – 26 October 1829) was a British mineralogist who became known for his practical approach to the discipline. (Full article...) -
Image 17John Sinkankas (May 15, 1915 – May 17, 2002) was a Navy officer and aviator, gemologist, gem carver and gem faceter, author of many books and articles on minerals and gemstones, and a bookseller and bibliographer of rare books. (Full article...)
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Image 18Werner Schreyer (14 November 1930 in Nuremberg; 12 February 2006 in Bochum) was a German mineralogist and experimental metamorphic petrologist. Schreyer completed his undergraduate work in geology and petrology at the University of Erlangen-Nuremberg, obtained his doctorate from the University of Munich in 1957, and in 1966 received his Habilitation from the University of Kiel. He was a professor at Ruhr University Bochum from 1966 to 1996. In 2002 Schreyer became the first German to be awarded the Mineralogical Society of America's highest honor, the Roebling Medal. Schreyer was a leading expert on phase relations in the MgO–Al2O3–SiO2–H2O (MASH) system, specializing in cordierite and minerals with equivalent chemical compositions, and high pressure and ultra high-pressure metamorphic mineral assemblages.
The mineral Schreyerite (V2Ti3O9) was named after Schreyer. (Full article...) -
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James Dwight Dana FRS FRSE (February 12, 1813 – April 14, 1895) was an American geologist, mineralogist, volcanologist, and zoologist. He made pioneering studies of mountain-building, volcanic activity, and the origin and structure of continents and oceans around the world.
His zoological author abbreviation is Dana. (Full article...) -
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Johann Nepomuk von Fuchs (15 May 1774 – 5 March 1856) was a German chemist and mineralogist, and royal Bavarian privy councillor. (Full article...) -
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Alexandra Navrotsky (born 20 June 1943 in New York City) is a physical chemist in the field of nanogeoscience. She is an elected member of the United States National Academy of Sciences (NAS) and the American Philosophical Society (APS). She was a board member of the Earth Sciences and Resources division of the NAS from 1995 until 2000.
In 2005, she was awarded the Urey Medal, by the European Association of Geochemistry.
In 2006, she was awarded the Harry H. Hess Medal, by the American Geophysical Union.
She is currently the director of NEAT ORU (Nanomaterials in Environment, Agriculture, and Technology Organized Research Unit), a primary program in nanogeoscience. She is distinguished professor at University of California, Davis. (Full article...) -
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Prof Gustavus ("Gustav") Rose FRSFor HFRSE (18 March 1798 – 15 July 1873) was a German mineralogist who was a native of Berlin. He was President of the German Geological Society from 1863 to 1873. (Full article...) -
Image 23James Freeman Dana (born in Amherst, New Hampshire, 23 September 1793; died in New York City, 14 April 1827) was an American chemist. (Full article...)
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Image 24Andrew Ketcham Barnett (1852–1914) was a mineral collector and dealer in Penzance, Cornwall, in the United Kingdom. He was Principal of the Penzance School of Mines (now part of the Camborne School of Mines), lectured on mining, and helped to build their mineral collection. He also served as Mayor of Penzance on seven occasions from 1906 to 1913.
Cooper writes of him:
:"Barnett was born in Chacewater, Cornwall in 1852. He was an original member of the Mineralogical Society, a Fellow of the Geological Society from 1875, and President of the Royal Geological Society of Cornwall 1907–08, having been awarded their Bolitho Medal in 1906. His classes on mineralogy in 1873 led to the establishment of the Mining and Science School at Penzance of which he became Principal. He was mayor of Penzance seven times from 1906 to 1913. Active as a mineral dealer from at least 1876 to 1887 at Chyandour, Penzance, he specialized in local specimens and occasionally sold minerals brought back from Australia by "Cousin Jack." In the 1881 Census he described himself as an assayer. He is the author of the now-rare Elementary Inorganic Chemistry; lecture notes, ca. 1900." (Full article...) -
Image 25Charles Thompson Prewitt (March 3, 1933 – April 28, 2022) was an American mineralogist and solid state chemist known for his work on structural chemistry of minerals and high-pressure chemistry. (Full article...)
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For editor resources and to collaborate with other editors on improving Wikipedia's Minerals-related articles, see WikiProject Rocks and minerals.
General images
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Image 4Pink cubic halite (NaCl; halide class) crystals on a nahcolite matrix (NaHCO3; a carbonate, and mineral form of sodium bicarbonate, used as baking soda). (from Mineral)
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Image 6Schist is a metamorphic rock characterized by an abundance of platy minerals. In this example, the rock has prominent sillimanite porphyroblasts as large as 3 cm (1.2 in). (from Mineral)
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Image 8Mohs Scale versus Absolute Hardness (from Mineral)
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Image 9Gypsum desert rose (from Mineral)
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Image 10An example of elbaite, a species of tourmaline, with distinctive colour banding. (from Mineral)
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Image 11Hübnerite, the manganese-rich end-member of the wolframite series, with minor quartz in the background (from Mineral)
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Image 12Black andradite, an end-member of the orthosilicate garnet group. (from Mineral)
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Image 13Red cinnabar (HgS), a mercury ore, on dolomite. (from Mineral)
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Image 14Sphalerite crystal partially encased in calcite from the Devonian Milwaukee Formation of Wisconsin (from Mineral)
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Image 16Epidote often has a distinctive pistachio-green colour. (from Mineral)
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Image 17When minerals react, the products will sometimes assume the shape of the reagent; the product mineral is termed a pseudomorph of (or after) the reagent. Illustrated here is a pseudomorph of kaolinite after orthoclase. Here, the pseudomorph preserved the Carlsbad twinning common in orthoclase. (from Mineral)
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Image 18Asbestiform tremolite, part of the amphibole group in the inosilicate subclass (from Mineral)
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Image 19Native gold. Rare specimen of stout crystals growing off of a central stalk, size 3.7 x 1.1 x 0.4 cm, from Venezuela. (from Mineral)
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Image 20Diamond is the hardest natural material, and has a Mohs hardness of 10. (from Mineral)
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Image 23Mohs hardness kit, containing one specimen of each mineral on the ten-point hardness scale (from Mohs scale)
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Image 24Perfect basal cleavage as seen in biotite (black), and good cleavage seen in the matrix (pink orthoclase). (from Mineral)
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Image 25Muscovite, a mineral species in the mica group, within the phyllosilicate subclass (from Mineral)
In the news
- 3 May 2024 –
- Panama bans First Quantum Minerals from extracting copper following the closure of its Cobre Panamá mine last year. (Reuters) (The Globe and Mail)
Did you know ...?
- ... that diamond (example pictured) is superhard but not supertough?
- ... that the minerals armalcolite, pyroxferroite and tranquillityite were discovered in lunar rocks?
- ... that the third key of alchemist Basil Valentine may describe a complex chemical process known as the volatilization of gold chloride?
Subcategories
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Topics
Overview | ||
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Common minerals |
Ore minerals, mineral mixtures and ore deposits | |||||||||
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Ores |
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Deposit types |
Borates | |||||
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Carbonates | |||||
Oxides |
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Phosphates | |||||
Silicates | |||||
Sulfides | |||||
Other |
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Crystalline | |||||||
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Cryptocrystalline | |||||||
Amorphous | |||||||
Miscellaneous | |||||||
Notable varieties |
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Oxide minerals |
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Silicate minerals | |||||
Other |
Gemmological classifications by E. Ya. Kievlenko (1980), updated | |||||||||
Jewelry stones |
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Jewelry-Industrial stones |
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Industrial stones |
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Mineral identification | |
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"Special cases" ("native elements and organic minerals") |
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"Sulfides and oxides" |
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"Evaporites and similars" |
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"Mineral structures with tetrahedral units" (sulfate anion, phosphate anion, silicon, etc.) |
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