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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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Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O. It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, drywall and blackboard or sidewalk chalk. Gypsum also crystallizes as translucent crystals of selenite. It forms as an evaporite mineral and as a hydration product of anhydrite. The Mohs scale of mineral hardness defines gypsum as hardness value 2 based on scratch hardness comparison.
Fine-grained white or lightly tinted forms of gypsum known as alabaster have been used for sculpture by many cultures including Ancient Egypt, Mesopotamia, Ancient Rome, the Byzantine Empire, and the Nottingham alabasters of Medieval England. (Full article...) -
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Zeolite is a family of several microporous, crystalline aluminosilicate materials commonly used as commercial adsorbents and catalysts. They mainly consist of silicon, aluminium, oxygen, and have the general formula Mn+
1/n(AlO
2)−
(SiO
2)
x・yH
2O where Mn+
1/n is either a metal ion or H+. These positive ions can be exchanged for others in a contacting electrolyte solution. H+
exchanged zeolites are particularly useful as solid acid catalysts.
The term was originally coined in 1756 by Swedish mineralogist Axel Fredrik Cronstedt, who observed that rapidly heating a material, believed to have been stilbite, produced large amounts of steam from water that had been adsorbed by the material. Based on this, he called the material zeolite, from the Greek ζέω (zéō), meaning "to boil" and λίθος (líthos), meaning "stone".
Zeolites occur naturally, but are also produced industrially on a large scale. , 253 unique zeolite frameworks have been identified, and over 40 naturally occurring zeolite frameworks are known. Every new zeolite structure that is obtained is examined by the International Zeolite Association Structure Commission (IZA-SC) and receives a three-letter designation. (Full article...) -
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Halite (/ˈhælaɪt, ˈheɪlaɪt/ HAL-yte, HAY-lyte), commonly known as rock salt, is a type of salt, the mineral (natural) form of sodium chloride (NaCl). Halite forms isometric crystals. The mineral is typically colorless or white, but may also be light blue, dark blue, purple, pink, red, orange, yellow or gray depending on inclusion of other materials, impurities, and structural or isotopic abnormalities in the crystals. It commonly occurs with other evaporite deposit minerals such as several of the sulfates, halides, and borates. The name halite is derived from the Ancient Greek word for "salt", ἅλς (háls). (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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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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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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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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Apatite is a group of phosphate minerals, usually hydroxyapatite, fluorapatite and chlorapatite, with high concentrations of OH−, F− and Cl− ion, respectively, in the crystal. The formula of the admixture of the three most common endmembers is written as Ca10(PO4)6(OH,F,Cl)2, and the crystal unit cell formulae of the individual minerals are written as Ca10(PO4)6(OH)2, Ca10(PO4)6F2 and Ca10(PO4)6Cl2.
The mineral was named apatite by the German geologist Abraham Gottlob Werner in 1786, although the specific mineral he had described was reclassified as fluorapatite in 1860 by the German mineralogist Karl Friedrich August Rammelsberg. Apatite is often mistaken for other minerals. This tendency is reflected in the mineral's name, which is derived from the Greek word ἀπατάω (apatáō), which means to deceive. (Full article...) -
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Fluorite (also called fluorspar) is the mineral form of calcium fluoride, CaF2. It belongs to the halide minerals. It crystallizes in isometric cubic habit, although octahedral and more complex isometric forms are not uncommon.
The Mohs scale of mineral hardness, based on scratch hardness comparison, defines value 4 as fluorite.
Pure fluorite is colourless and transparent, both in visible and ultraviolet light, but impurities usually make it a colorful mineral and the stone has ornamental and lapidary uses. Industrially, fluorite is used as a flux for smelting, and in the production of certain glasses and enamels. The purest grades of fluorite are a source of fluoride for hydrofluoric acid manufacture, which is the intermediate source of most fluorine-containing fine chemicals. Optically clear transparent fluorite has anomalous partial dispersion, that is, its refractive index varies with the wavelength of light in a manner that differs from that of commonly used glases, so fluorite is useful in making apochromatic lenses, making it valuable, particularly in photographic optics. Fluorite optics are also usable in the far-ultraviolet and mid-infrared ranges, where conventional glasses are too opaque for use. Fluorite also has low dispersion, and a high refractive index for its density, which can make it useful for some specialized purposes in optics. (Full article...) -
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Opal is a hydrated amorphous form of silica (SiO2·nH2O); its water content may range from 3% to 21% by weight, but is usually between 6% and 10%. Due to its amorphous property, it is classified as a mineraloid, unlike crystalline forms of silica, which are considered minerals. It is deposited at a relatively low temperature and may occur in the fissures of almost any kind of rock, being most commonly found with limonite, sandstone, rhyolite, marl, and basalt.
The name opal is believed to be derived from the Sanskrit word upala (उपल), which means 'jewel', and later the Greek derivative opállios (ὀπάλλιος).
There are two broad classes of opal: precious and common. Precious opal displays play-of-color (iridescence); common opal does not. Play-of-color is defined as "a pseudo chromatic optical effect resulting in flashes of colored light from certain minerals, as they are turned in white light." The internal structure of precious opal causes it to diffract light, resulting in play-of-color. Depending on the conditions in which it formed, opal may be transparent, translucent, or opaque, and the background color may be white, black, or nearly any color of the visual spectrum. Black opal is considered the rarest, while white, gray, and green opals are the most common. (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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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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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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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...) -
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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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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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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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Chalcopyrite (/ˌkælkəˈpaɪˌraɪt, -koʊ-/ KAL-kə-PY-ryte, -koh-) is a copper iron sulfide mineral and the most abundant copper ore mineral. It has the chemical formula CuFeS2 and crystallizes in the tetragonal system. It has a brassy to golden yellow color and a hardness of 3.5 to 4 on the Mohs scale. Its streak is diagnostic as green-tinged black.
On exposure to air, chalcopyrite tarnishes to a variety of oxides, hydroxides, and sulfates. Associated copper minerals include the sulfides bornite (Cu5FeS4), chalcocite (Cu2S), covellite (CuS), digenite (Cu9S5); carbonates such as malachite and azurite, and rarely oxides such as cuprite (Cu2O). It is rarely found in association with native copper. Chalcopyrite is a conductor of electricity.
Copper can be extracted from chalcopyrite ore using various methods. The two predominant methods are pyrometallurgy and hydrometallurgy, the former being the most commercially viable. (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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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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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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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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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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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...)
Selected mineralogist
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Johannes Martin Bijvoet ForMemRS (23 January 1892, Amsterdam – 4 March 1980, Winterswijk) was a Dutch chemist and crystallographer at the van 't Hoff Laboratory at Utrecht University. He is famous for devising a method of establishing the absolute configuration of molecules. In 1946, he became member of the Royal Netherlands Academy of Arts and Sciences.
The concept of tetrahedrally bound carbon in organic compounds stems back to the work by van 't Hoff and Le Bel in 1874. At this time, it was impossible to assign the absolute configuration of a molecule by means other than referring to the projection formula established by Fischer, who had used glyceraldehyde as the prototype and assigned randomly its absolute configuration. (Full article...) -
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Franz Ludwig von Cancrin (February 21, 1738 in Breidenbach – 1812) was a German mineralogist, metallurgist, architect and writer.
He was born into a German mining family where he was trained by his father in the science of mining. In 1764, he entered the service of the landgrave of Hesse-Kassel at Hanau, becoming professor of mathematics at the military academy, head of the civil engineering department of the state, director of the theatre and (1774) of the mint. A work on the copper mines of Elesse (1767) earned him a European reputation, and in 1783 he accepted from Catherine II of Russia the directorship of the famous Staraya salt-works, living thenceforth in Russia. (Full article...) -
Image 3Wilhelm Hermann Julius Eitel (6 May 1891, Frankfurt am Main – 20 July 1979, United States) was a German-American scientist. (Full article...)
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Friedrich August Walchner (2 September 1799 – 17 February 1865) was a German geologist, chemist and mineralogist. (Full article...) -
Image 5Johann Gottlob von Kurr (15 January 1798, Sulzbach an der Murr – 9 May 1870, Stuttgart) was a German pharmacist and naturalist, making contributions in the fields of botany and mineralogy.
He worked for several years as a pharmacist in Calw and other communities, then later studied medicine and surgery at the University of Tübingen, where in 1832 he received doctorates for both disciplines. From 1832 to 1870 he taught classes in natural history at the vocational school in Stuttgart (in 1841 it became known as a polytechnic institute). He was a member of the Vereins für vaterländische Naturkunde in Württemberg (Association for Natural History in Württemberg), and from 1844, was curator of its geognostic-paleontological collections. (Full article...) -
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Harry von Eckermann (1886–1969) was a Swedish industrialist, mineralogist and geologist. His studies were centered around anorogenic alkaline igneous rocks occurring in the Baltic Shield. Following this line he studied the Alnö Complex, Norra Kärr Alkaline Complex and various Rapakivi granites.
In a 1948 publication on Alnö, von Eckermann correctly claimed a magmatic origin of carbonatite, albeit his finds were only widely accepted after the Ol Doinyo Lengai eruption of carbonatite lava in the 1960s showed contemporary evidence on the existence of such magmas. In relation to the mid-20th century granitization controversy von Eckermann rejected the notion that rapakivi granites were Jotnian sediments turned into granite. (Full article...) -
Image 7João da Silva Barbosa or João da Silva Feijó, (1760 in Rio de Janeiro – 1824), was a naturalist, mineralogist and Portuguese soldier, born in Brazil.
João da Silva Feijó studied philosophy and mathematics at the University of Coimbra and adopted the name Feijó in homage to Benito Jerónimo Feijoo, Spanish philosopher, who at the time was respected among natural history students. (Full article...) -
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Georgius Agricola (/əˈɡrɪkələ/; born Georg Bauer; 24 March 1494 – 21 November 1555) was a German Humanist scholar, mineralogist and metallurgist. Born in the small town of Glauchau, in the Electorate of Saxony of the Holy Roman Empire, he was broadly educated, but took a particular interest in the mining and refining of metals. He was the first to drop the Arabic definite article al-, exclusively writing chymia and chymista in describing activity that we today would characterize as chemical or alchemical, giving chemistry its modern name. For his groundbreaking work De Natura Fossilium published in 1546, he is generally referred to as the Father of Mineralogy and the founder of geology as a scientific discipline.
He is well known for his pioneering work De re metallica libri XII, that was published in 1556, one year after his death. This 12-volume work is a comprehensive and systematic study, classification and methodical guide on all available factual and practical aspects, that are of concern for mining, the mining sciences and metallurgy, investigated and researched in its natural environment by means of direct observation. Unrivalled in its complexity and accuracy, it served as the standard reference work for two centuries. Agricola stated in the preface, that he will exclude "all those things which I have not myself seen, or have not read or heard of". He continued, "That which I have neither seen, nor carefully considered after reading or hearing of, I have not written about." (Full article...) -
Image 9Vesselina Vassileva Breskovska (Bulgarian: Веселина Василева Бресковска) (December 6, 1928, Granit, Stara Zagora Province, Bulgaria – August 12, 1997, Sofia, Bulgaria) was a 20th-century Bulgarian geologist, mineralogist and crystallographer. (Full article...)
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Niels Steensen (Danish: Niels Steensen; Latinized to Nicolas Steno or Nicolaus Stenonius); 1 January 1638 – 25 November 1686 [NS: 11 January 1638 – 5 December 1686]) was a Danish scientist, a pioneer in both anatomy and geology who became a Catholic bishop in his later years.
Steensen was trained in the classical texts on science; however, by 1659 he seriously questioned accepted knowledge of the natural world. Importantly he questioned explanations for tear production, the idea that fossils grew in the ground and explanations of rock formation. His investigations and his subsequent conclusions on fossils and rock formation have led scholars to consider him one of the founders of modern stratigraphy and modern geology. The importance of Steensen's foundational contributions to geology may be gauged from the fact that half of the twenty papers in a recent miscellany volume on The Revolution in Geology from the Renaissance to the Enlightenment focus on Steensen, the "preeminent Baroque polymath and founder of modern geologic thought". (Full article...) -
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Thomas Thomson MD FRS FLS FRSE (12 April 1773 – 2 August 1852) was a Scottish chemist and mineralogist whose writings contributed to the early spread of Dalton's atomic theory. His scientific accomplishments include the invention of the saccharometer and he gave silicon its current name. He served as president of the Philosophical Society of Glasgow.
Thomson was the father of the botanist Thomas Thomson, and the uncle and father-in-law of the Medical Officer of Health Robert Thomson. (Full article...) -
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Franz Xaver Maximilian Zippe (František Xaver Zippe) (15 January 1791 – 22 February 1863), was a Bohemian natural philosopher, scientist and mineralogist. (Full article...) -
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Ho-Kwang (Dave) Mao (Chinese: 毛河光; pinyin: Máo Héguāng; Wade–Giles: Mao Ho-kuang; born June 18, 1941) is a Chinese-American geologist. He is the director of the Center for High Pressure Science and Technology Advanced Research in Shanghai, China. He was a staff scientist at Geophysical Laboratory of the Carnegie Institution for Science for more than 30 years. Mao is a recognized leading scientist in high pressure geosciences and physical science. There are two minerals named after him, Davemaoite and Maohokite. (Full article...) -
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George Washington Carpenter (July 31, 1802 – June 7, 1860) was an American scientist. (Full article...) -
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Carl Franz Anton Ritter von Schreibers (15 August 1775 – 21 May 1852) was an Austrian naturalist who was a native of Pressburg, Hungary, Habsburg Empire (today Bratislava, Slovakia).
In 1847, an uncommon iron-nickel-phosphide ((Fe,Ni)3P) mineral was named in his honor by Wilhelm Karl Ritter von Haidinger (1775–1871). The mineral is found in meteorites, and is known today as schreibersite. As a zoologist, he was the first to perform a comprehensive anatomical study of the olm, a cave-dwelling, aquatic amphibian. The plant genus Schreibersia (synonym Augusta, family Rubiaceae) was named in his honor by Johann Baptist Emanuel Pohl. The common bent-wing bat (Miniopterus schreibersii), also known as the Schreibers's long-fingered bat or Schreibers's bat, is a species of insectivorous bat. They appear to have dispersed from a subtropical origin and distributed throughout the southern Palearctic, Ethiopic, Oriental, and Australian regions. In Europe, it is present in the southern half on the continent from Iberia to the Caucasus, with the largest populations found in the warmer Mediterranean area. The common and scientific names honor Carl Franz Anton Ritter von Schreibers. (Full article...) -
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Franz Xaver Freiherr von Wulfen (5 November 1728 – 17 March 1805) was an Austrian botanist, zoologist, mineralogist, alpinist, and Jesuit priest. He is credited with discovering the flowering plants Wulfenia carinthiaca, Saxifraga moschata, and Stellaria bulbosa. In 1845 the lead molybdate mineral wulfenite was named in his honor by Wilhelm Karl von Haidinger. (Full article...) -
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Adolph Knopf (December 2, 1882 – November 23, 1966) was an American geologist. Educated at the University of California, Berkeley, he held professional appointments at the United States Geological Survey, Yale University, and Stanford University. He was primarily a petrologist and mineralogist, though later in his career contributed to geochronology. He performed much of his field work in the western United States, investigating mineral deposits in Alaska, the Boulder Batholith in Montana, and the Gold Country of California.
Knopf was a member of the National Academy of Sciences and the American Academy of Arts and Sciences. He served as president of the Geological Society of America in 1944 and received its Penrose Medal in 1959. His second wife, Eleanora Knopf, was a notable geologist and frequent collaborator. (Full article...) -
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Arthur Moritz Schoenflies (German: [ˈʃøːnfliːs]; 17 April 1853 – 27 May 1928), sometimes written as Schönflies, was a German mathematician, known for his contributions to the application of group theory to crystallography, and for work in topology.
Schoenflies was born in Landsberg an der Warthe (modern Gorzów, Poland). Arthur Schoenflies married Emma Levin (1868–1939) in 1896. He studied under Ernst Kummer and Karl Weierstrass, and was influenced by Felix Klein. (Full article...) -
Image 19Franz-Joseph Müller, Freiherr von Reichenstein or Franz-Joseph Müller von Reichenstein (1 July 1740 or 4 October 1742 – 12 October 1825 or 1826) was an Austrian mineralogist and mining engineer. Müller held several positions in the Habsburg monarchy administration of mines and coinage in the Banat, Transylvania, and Tyrol. During his time in Transylvania he discovered tellurium in 1782. In his later career he became a member of the imperial council in Vienna and was knighted and elevated to the rank Freiherr in 1820. (Full article...)
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Gerhard vom Rath (20 August 1830 – 23 April 1888), was a German mineralogist, born at Duisburg in Prussia. (Full article...) -
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Pierre Louis Antoine Cordier (31 March 1777 – 30 March 1861) was a French geologist and mineralogist, and a founder of the French Geological Society. He was professor of geology at the Muséum national d'histoire naturelle in Paris from 1819 to 1861, and was responsible for the development of the geological gallery in the museum. (Full article...) -
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Paul Gabriel Hautefeuille (2 December 1836 in Étampes – 8 December 1902 in Paris) was a French mineralogist and chemist. (Full article...) -
Image 24Rudolf Koechlin (11 November 1862 – 11 February 1939) was an Austrian mineralogist.
Koechlin was born and died in Vienna. He studied mineralogy, crystallography, petrology and geology at the University of Vienna, obtaining his doctorate in 1887 with a thesis on manganite, polianite and pyrolusite. At Vienna, his instructors included Gustav Tschermak and Albrecht Schrauf. In 1884 he began work as a volunteer in the mineralogical-petrography department of the Naturhistorisches Hofmuseum in Vienna. In 1897 he became a "custos-adjunct", later named a curator first-class (1912), and in 1920, was appointed director of the mineralogical-petrography department. (Full article...) -
Image 25Josef Zemann (25 May 1923 – 16 October 2022) was an Austrian mineralogist and geologist. (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 2Native 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 4Diamond is the hardest natural material, and has a Mohs hardness of 10. (from Mineral)
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Image 6Sphalerite crystal partially encased in calcite from the Devonian Milwaukee Formation of Wisconsin (from Mineral)
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Image 8Muscovite, a mineral species in the mica group, within the phyllosilicate subclass (from Mineral)
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Image 9Black andradite, an end-member of the orthosilicate garnet group. (from Mineral)
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Image 11When 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 13An example of elbaite, a species of tourmaline, with distinctive colour banding. (from Mineral)
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Image 14Schist 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 15Pink 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 16Hübnerite, the manganese-rich end-member of the wolframite series, with minor quartz in the background (from Mineral)
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Image 17Mohs Scale versus Absolute Hardness (from Mineral)
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Image 18Epidote often has a distinctive pistachio-green colour. (from Mineral)
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Image 19Asbestiform tremolite, part of the amphibole group in the inosilicate subclass (from Mineral)
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Image 21Mohs hardness kit, containing one specimen of each mineral on the ten-point hardness scale (from Mohs scale)
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Image 23Perfect basal cleavage as seen in biotite (black), and good cleavage seen in the matrix (pink orthoclase). (from Mineral)
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Image 24Red cinnabar (HgS), a mercury ore, on dolomite. (from Mineral)
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Image 25Gypsum desert rose (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 the Lewisian gneiss (pictured), forms the basement to Torridonian and Cambro-Ordovician sedimentary rocks in the Hebridean Terrane?
- ... that abernathyite is both fluorescent and radioactive and is named for the mine operator who discovered it?
- ... that the minerals armalcolite, pyroxferroite and tranquillityite were discovered in lunar rocks?
- ...that the streak of a mineral, the color of the mark it makes when rubbed on a plate, is usually a more consistent identifier than the color of the original mineral?
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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