Portal:Minerals
![]() | Portal maintenance status: (May 2019)
|
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
-
Image 1A sample of andesite (dark groundmass) with amygdaloidal vesicles filled with zeolite. Diameter of view is 8 cm.
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...) -
Image 2
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...) -
Image 3
Crystal structure of table salt (sodium in purple, chlorine in green)
In crystallography, crystal structure is a description of ordered arrangement of atoms, ions, or molecules in a crystalline material. Ordered structures occur from intrinsic nature of constituent particles to form symmetric patterns that repeat along the principal directions of three-dimensional space in matter.
The smallest group of particles in material that constitutes this repeating pattern is unit cell of the structure. The unit cell completely reflects symmetry and structure of the entire crystal, which is built up by repetitive translation of unit cell along its principal axes. The translation vectors define the nodes of Bravais lattice.
The lengths of principal axes/edges, of unit cell and angles between them are lattice constants, also called lattice parameters or cell parameters. The symmetry properties of crystal are described byconcept of space groups. All possible symmetric arrangements of particles in three-dimensional space may be described by 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...) -
Image 4
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...) -
Image 5
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...) -
Image 6
Graphite (/ˈɡræfaɪt/) is a crystalline form of the element carbon. It consists of stacked layers of graphene. Graphite occurs naturally and is the most stable form of carbon under standard conditions. Synthetic and natural graphite are consumed on a large scale (1.3 million metric tons per year in 2022) for uses in pencils, lubricants, and electrodes. Under high pressures and temperatures it converts to diamond. It is a good (but not excellent) conductor of both heat and electricity. (Full article...) -
Image 7Halite from the Wieliczka salt mine, Małopolskie, Poland
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...) -
Image 8Quartz crystal cluster from Brazil
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...) -
Image 9
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...) -
Image 10
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...) -
Image 11
A crystalline solid: atomic resolution image of strontium titanate. Brighter spots are columns of strontium atoms and darker ones are titanium-oxygen columns.
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 many of its subareas, such as X-ray crystallography, are themselves important scientific topics. Crystallography ranges from the fundamentals of crystal structure to the mathematics of crystal geometry, including those that are not periodic or quasicrystals. At the atomic scale it can involve the use of X-ray diffraction to produce experimental data that the tools of X-ray crystallography can convert into detailed positions of atoms, and sometimes electron density. At larger scales 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 biology, chemistry, and physics, as well new developments in these fields. (Full article...) -
Image 12A ruby crystal from Dodoma Region, Tanzania
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, which sold for US$34.8 million. (Full article...) -
Image 13
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...) -
Image 14
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...) -
Image 15The 423-carat (85 g) blue Logan Sapphire
Sapphire is a precious gemstone, a variety of the mineral corundum, consisting of aluminium oxide (α-Al2O3) with trace amounts of elements such as iron, titanium, cobalt, lead, chromium, vanadium, magnesium, boron, and silicon. The name sapphire is derived from the Latin word sapphirus, itself from the Greek word sappheiros (σάπφειρος), which referred to lapis lazuli. It is typically blue, but natural "fancy" sapphires also occur in yellow, purple, orange, and green colors; "parti sapphires" show two or more colors. Red corundum stones also occur, but are called rubies rather than sapphires. Pink-colored corundum may be classified either as ruby or sapphire depending on the locale. Commonly, natural sapphires are cut and polished into gemstones and worn in jewelry. They also may be created synthetically in laboratories for industrial or decorative purposes in large crystal boules. Because of the remarkable hardness of sapphires – 9 on the Mohs scale (the third hardest mineral, after diamond at 10 and moissanite at 9.5) – sapphires are also used in some non-ornamental applications, such as infrared optical components, high-durability windows, wristwatch crystals and movement bearings, and very thin electronic wafers, which are used as the insulating substrates of special-purpose solid-state electronics such as integrated circuits and GaN-based blue LEDs. Sapphire is the birthstone for September and the gem of the 45th anniversary. A sapphire jubilee occurs after 65 years. (Full article...) -
Image 16Beachy Head is a part of the extensive Southern England Chalk Formation.
Chalk is a soft, white, porous, sedimentary carbonate rock. It is a form of limestone composed of the mineral calcite and originally formed deep under the sea by the compression of microscopic plankton that had settled to the sea floor. Chalk is common throughout Western Europe, where deposits underlie parts of France, and steep cliffs are often seen where they meet the sea in places such as the Dover cliffs on the Kent coast of the English Channel.
Chalk is mined for use in industry, such as for quicklime, bricks and builder's putty, and in agriculture, for raising pH in soils with high acidity. It is also used for "blackboard chalk" for writing and drawing on various types of surfaces, although these can also be manufactured from other carbonate-based minerals, or gypsum. (Full article...) -
Image 17Amethyst cluster from Artigas, Uruguay
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...) -
Image 18
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. In Roman times, cinnabar was highly valued as paint for walls, especially interiors, since it darkened when used outdoors due to exposure to sunlight.
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...) -
Image 19
Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Diamond as a form of carbon is a tasteless, odourless, strong, and brittle solid that is transparent in colour, a poor conductor of electricity, and insoluble in water. 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...) -
Image 20
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...) -
Image 21Malachite from the Democratic Republic of the Congo
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...) -
Image 22Brazilian trigonal hematite crystal
Hematite (/ˈhiːməˌtaɪt, ˈhɛmə-/), also spelled as haematite, is a common iron oxide compound with the formula, Fe2O3 and is widely found in rocks and soils. Hematite crystals belong to the rhombohedral lattice system which is designated the alpha polymorph of Fe
2O
3. It has the same crystal structure as corundum (Al
2O
3) and ilmenite (FeTiO
3). With this it forms a complete solid solution at temperatures above 950 °C (1,740 °F).
Hematite naturally occurs in black to steel or silver-gray, brown to reddish-brown, or red colors. It is mined as an important ore mineral of iron. It is electrically conductive. Hematite varieties include kidney ore, martite (pseudomorphs after magnetite), iron rose and specularite (specular hematite). While these forms vary, they all have a rust-red streak. Hematite is not only harder than pure iron, but also much more brittle. Maghemite is a polymorph of hematite (γ-Fe
2O
3) with the same chemical formula, but with a spinel structure like magnetite.
Large deposits of hematite are found in banded iron formations. Gray hematite is typically found in places that have still, standing water or mineral hot springs, such as those in Yellowstone National Park in North America. The mineral can precipitate in the water and collect in layers at the bottom of the lake, spring, or other standing water. Hematite can also occur in the absence of water, usually as the result of volcanic activity.
Clay-sized hematite crystals can also occur as a secondary mineral formed by weathering processes in soil, and along with other iron oxides or oxyhydroxides such as goethite, which is responsible for the red color of many tropical, ancient, or otherwise highly weathered soils. (Full article...) -
Image 23
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...) -
Image 24
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...) -
Image 25
Zeolite exhibited in the Estonian Museum of Natural History
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...)
Selected mineralogist
-
Image 1Ralph 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...)
-
Image 2
Nikolay Vasilyevich Belov (Russian: Никола́й Васи́льевич Бело́в; December 14, 1891 – March 6, 1982) was a Soviet and Russian crystallographer, geochemist, academician (1953), and Hero of Socialist Labour (1969).
Belov worked primarily in the fields of mineralogy (particularly silicates), determination of crystal structures using X-ray crystallography, and the theory of symmetry, specifically dichromatic, and polychromatic symmetry, a field which Belov founded. (Full article...) -
Image 3Bust of Shen at the Beijing Ancient Observatory
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 4
Karl August Lossen
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...) -
Image 5Adolarius Jacob Forster (1739–1806) was a Prussian mineralogist and dealer in display specimen minerals. The Forster family left Yorkshire in 1649 and settled in Prussia. Adolarius Jacob Forster began dealing in mineral specimens around 1766, at the age of 27. He continued in that profession for 40 years and travelled widely. He had premises in London, Paris and St. Petersburg. The Covent Garden, London shop and one in Soho was run by his wife. His brother, Ingham Henry Forster (1725–1782) ran the business in Paris. Auction catalogues for sales in Paris were written by Romé de l'Isle.
He was related to Johann Georg Adam Forster and Johann Reinhold Forster and his sister married the London dealer naturalist George Humphrey at St-Martin-in-the-Fields, London on August 16, 1768. In 1802 Forster sold a collection to the museum of the St Petersburg Mining Institute, under the auspices of the Emperor of All Russia Alexander I. He spent the last ten years of his life in Russia, and died in St. Petersburg in 1806. The dealership was taken over by his nephew John Henry Heuland. (Full article...) -
Image 6Westgarth Forster (1772–1835) was a geologist and mining engineer, mine agent at Allenheads and Coalcleugh (Northumberland) over two decades and then a consultant surveyor and author. He was the son of a mining engineer (Westgarth Forster the elder, 1738–1797), and was born in Coalcleugh, Northumberland. (Full article...)
-
Image 7
James Smithson FRS (c. 1765 – 27 June 1829) was a British chemist and mineralogist. He published numerous scientific papers for the Royal Society during the early 1800s as well as defining calamine, which would eventually be renamed after him as "smithsonite". He was the founding donor of the Smithsonian Institution, which also bears his name.
Born in Paris, France, as the illegitimate child of Elizabeth Hungerford Keate Macie and Hugh Percy (born Hugh Smithson), the 1st Duke of Northumberland, he was given the French name Jacques-Louis Macie. His birth date was not recorded and the exact location of his birth is unknown; it is possibly in the Pentemont Abbey. Shortly after his birth he naturalized to Britain where his name was anglicized to James Louis Macie. He adopted his father's original surname of Smithson in 1800, following his mother's death. He attended university at Pembroke College, Oxford in 1782, eventually graduating with a Master of Arts in 1786. As a student he participated in a geological expedition to Scotland and studied chemistry and mineralogy. Highly regarded for his blowpipe analysis and his ability to work in miniature, Smithson spent much of his life traveling extensively throughout Europe; he published some 27 papers in his life. (Full article...) -
Image 8For the French Napoleonic War General see Marshall Étienne Macdonald
Marshall McDonald (October 18, 1835 – September 1, 1895) was an American engineer, geologist, mineralogist, pisciculturist, and fisheries scientist. McDonald served as the commissioner of the United States Commission of Fish and Fisheries from 1888 until his death in 1895. He is best known for his inventions of a number of fish hatching apparatuses and a fish ladder that enabled salmon and other migrating fish species to ascend the rapids of watercourses resulting in an increased spawning ground. McDonald's administration of the U.S. Commission of Fish and Fisheries was notably free of scandal and furthered the "protection and culture" of fish species throughout the United States. (Full article...) -
Image 9
Alexander von Schrenk
Alexander Gustav von Schrenk (4 February 1816 – 25 June 1876) was a Baltic German-Russian naturalist born near Tula in what was then the Russian Empire. He was a brother to zoologist Leopold von Schrenck (1826–1894).
From 1834 to 1837, he studied sciences at the University of Dorpat (Tartu), later spending several years as an assistant at the botanical garden in St. Petersburg. He was habilitated for mineralogy at Dorpat, where from 1849 he served as a lecturer. From 1858 he spent the next ten years at his wife's manor in Pühajärve (Heiligensee), Livonia, returning to Dorpat in 1868, where he died several years later. (Full article...) -
Image 10
John Scouler
John Scouler (31 December 1804 – 13 November 1871) was a Scottish naturalist. (Full article...) -
Image 11Arthur Hutchinson by Sir William Rothenstein
Arthur Hutchinson OBE FRS (6 July 1866 – 12 December 1937) was a British mineralogist. During World War I, and at the request of the Admiralty, he was asked to design gas masks suitable for the Navy; for his work, he was awarded the OBE. Hutchinson was elected a Fellow of the Royal Society in 1922. He was master of Pembroke College, Cambridge, from 1928 to 1937, served on the Council of the Royal Society from 1932 to 1934, and was the Society's Vice-President for the year 1933-34. (Full article...) -
Image 12
Archdeacon Joseph Campbell, 1923
Joseph Campbell (1856–1933) was an Anglican priest and mineralogist in Australia. Campbell was a recognised authority on geology and served as a consulting engineer in both Queensland and New South Wales. He was an expert on gemstones and wrote several books on the subject. (Full article...) -
Image 13
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...) -
Image 14
Félix Pisani (1831–1920)
Félix Pisani (28 April 1831, Constantinople – 7 November 1920, Paris) was a French chemist and mineralogist.
He was born in Istanbul, where his Venetian father worked in the Russian diplomatic service. Beginning in 1854, he studied chemistry in Paris at a private school run by Charles Frédéric Gerhardt (1816–1856). (Full article...) -
Image 15
Leonid Alekseyevich Kulik (Russian: Леонид Алексеевич Кулик; 19 August 1883 – 14 or 24 April 1942) was a Soviet mineralogist who is noted for his research into meteorites. (Full article...) -
Image 16Émile Bertrand (1844–1909) was a French mineralogist, in honour of whom bertrandite was named by Alexis Damour. He also gave his name to the Bertrand lens or phase telescope.
He studied at the Ecole des Mines in Paris and was a co-founder of the Société française de minéralogie et de cristallographie [fr]. He wrote a book on the application of microscopy to mineralogical studies, "De l'Application du microscope à l'étude de la minéralogie" (1878); published a translation of Ernst Mach's work on the history of mechanics, "La mécanique: exposé historique et critique de son développement" (1904); and is credited with the design of a refractometer. (Full article...) -
Image 17François Alluaud (21 September 1778, Limoges – 18 February 1866, Limoges) was a French manufacturer of Limoges porcelain, geologist and mineralogist. He was the grandfather of entomologist Charles Alluaud (1861–1949).
Following the death of his father in 1799, who was also named François Alluaud, he took over ownership of the family porcelain factory in Limoges. The company operated its own quarries; a feldspar mine at Chanteloube and a kaolin quarry at Marcognac. (Full article...) -
Image 18João 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...) -
Image 19
Johann Nepomuk von Fuchs (15 May 1774 – 5 March 1856) was a German chemist and mineralogist, and royal Bavarian privy councillor. (Full article...) -
Image 20Bertram Eugene Warren (June 28, 1902 – June 27, 1991) was an American crystallographer. His studies of X-rays provided much knowledge and understanding of both crystalline and non-crystalline materials. He also worked on changing amorphous solids to a crystalline state. (Full article...)
-
Image 21
Johann Carl Gehler (17 May 1732 – 6 May 1796) was a German physician, mineralogist, and anatomist.
Born 17 May 1732 in Görlitz, Gehler studied medicine from 1751 to 1758 at the University of Leipzig, where he was a pupil of physician and botanist Christian Gottlieb Ludwig. While a student at Leipzig, he furthered his interest in natural sciences, publishing the mineralogical treatise, De characteribus fossilium externis (1757), as a result. Following graduation, he continued his education by studying mineralogy in Freiberg and obstetrics in Strasbourg as a student of Johann Jakob Fried (1689–1769). (Full article...) -
Image 22
Johann Friedrich Ludwig Hausmann
Johann Friedrich Ludwig Hausmann (22 February 1782, Hannover – 26 December 1859, Göttingen) was a German mineralogist. (Full article...) -
Image 23Jean-André Mongez (21 November 1750 – May 1788) was a French priest and mineralogist. He is presumed to have died at Vanikoro, on the La Pérouse expedition. (Full article...)
-
Image 24Adolf Pabst (30 November 1899, Chicago – 3 April 1990, Berkeley, California) was an American mineralogist and geologist. (Full article...)
-
Image 25Francis John Turner (10 April 1904 – 21 December 1985) was a New Zealand geologist. He received his BSc and MSc from the Auckland University College. He worked with the New Zealand Geological Survey and in 1926 he became a geology lecturer in the University of Otago.
At Otago he became interested in metamorphism and studied the unexplored metamorphic rocks of South Island on which he earned his PhD in 1934 from the University of New Zealand. His application and expansion of Pentti Eskola's concept of metamorphic facies led to his publication of Mineralogical and Structural Evolution of Metamorphic Rocks, the book that established his position in the field of petrology and was a great influence on a generation of geologists. (Full article...)
Related portals
Get involved
For editor resources and to collaborate with other editors on improving Wikipedia's Minerals-related articles, see WikiProject Rocks and minerals.
General images
-
Image 1Red cinnabar (HgS), a mercury ore, on dolomite. (from Mineral)
-
Image 2Schist 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)
-
Image 3Mohs Scale versus Absolute Hardness (from Mineral)
-
Image 4An example of elbaite, a species of tourmaline, with distinctive colour banding. (from Mineral)
-
Image 5When 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)
-
Image 7Muscovite, a mineral species in the mica group, within the phyllosilicate subclass (from Mineral)
-
Image 9Hübnerite, the manganese-rich end-member of the wolframite series, with minor quartz in the background (from Mineral)
-
Image 11Diamond is the hardest natural material, and has a Mohs hardness of 10. (from Mineral)
-
Image 14Sphalerite crystal partially encased in calcite from the Devonian Milwaukee Formation of Wisconsin (from Mineral)
-
Image 15Epidote often has a distinctive pistachio-green colour. (from Mineral)
-
Image 18Pink 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)
-
Image 20Asbestiform tremolite, part of the amphibole group in the inosilicate subclass (from Mineral)
-
Image 21Native 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)
-
Image 22Mohs hardness kit, containing one specimen of each mineral on the ten-point hardness scale (from Mohs scale)
-
Image 24Gypsum desert rose (from Mineral)
-
Image 25Perfect basal cleavage as seen in biotite (black), and good cleavage seen in the matrix (pink orthoclase). (from Mineral)
-
Image 26Black andradite, an end-member of the orthosilicate garnet group. (from Mineral)
Did you know ...?
- ... that after a mine tunnel was dug near Cerro de Pasco, Peru, the first known specimen of pascoite (example pictured) formed on the walls?
- ... that the name of mineral scrutinyite reflects the efforts spent to distinguish it from plattnerite – another form of lead dioxide?
- ... that the crystal symmetry of melanophlogite changes depending on the guests trapped inside it?
- ... that the mineral messelite was described in 1890, discredited in 1940, reinstated and named neomesselite in 1955, and named messelite once again by 1959?
Subcategories
Topics
Overview | ||
---|---|---|
Common minerals |
Ore minerals, mineral mixtures and ore deposits | |||||||||
---|---|---|---|---|---|---|---|---|---|
Ores |
| ||||||||
Deposit types |
Borates | |||||
---|---|---|---|---|---|
Carbonates | |||||
Oxides |
| ||||
Phosphates | |||||
Silicates | |||||
Sulfides | |||||
Other |
|
Crystalline | |||||||
---|---|---|---|---|---|---|---|
Cryptocrystalline | |||||||
Amorphous | |||||||
Miscellaneous | |||||||
Notable varieties |
|
Oxide minerals |
| ||||
---|---|---|---|---|---|
Silicate minerals | |||||
Other |
Gemmological classifications by E. Ya. Kievlenko (1980), updated | |||||||||
Jewelry stones |
| ||||||||
Jewelry-Industrial stones |
| ||||||||
Industrial stones |
| ||||||||
Mineral identification | |
---|---|
"Special cases" ("native elements and organic minerals") |
|
---|---|
"Sulfides and oxides" |
|
"Evaporites and similars" |
|
"Mineral structures with tetrahedral units" (sulfate anion, phosphate anion, silicon, etc.) |
|
Associated Wikimedia
The following Wikimedia Foundation sister projects provide more on this subject:
-
Commons
Free media repository -
Wikibooks
Free textbooks and manuals -
Wikidata
Free knowledge base -
Wikinews
Free-content news -
Wikiquote
Collection of quotations -
Wikisource
Free-content library -
Wikiversity
Free learning tools -
Wiktionary
Dictionary and thesaurus
References
- Pages using Template:Post-nominals with customized linking
- Manually maintained portal pages from May 2019
- All manually maintained portal pages
- Portals with triaged subpages from May 2019
- All portals with triaged subpages
- Portals with named maintainer
- Automated article-slideshow portals with 31–40 articles in article list
- Automated article-slideshow portals with 201–500 articles in article list
- Portals needing placement of incoming links