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55-627: The word entered English by way of either Swedish ( trona ) or Spanish ( trona ), with both possible sources having the same meaning as in English: the mineral natron from North Africa. Both the Spanish and Swedish terms derive from the Arabic trōn , which in turn derives from Arabic natron and Hebrew נתרן ( natruna ), which comes from ancient Greek νιτρον ( nitron ), derived ultimately from ancient Egyptian ntry (or nitry'’). Trona

110-444: A ( polarizer ) below the sample and an analyzer above it, polarized perpendicular to each other. Light passes successively through the polarizer, the sample and the analyzer. If there is no sample, the analyzer blocks all the light from the polarizer. However, an anisotropic sample will generally change the polarization so some of the light can pass through. Thin sections and powders can be used as samples. When an isotropic crystal

165-548: A polarizing microscope . James D. Dana published his first edition of A System of Mineralogy in 1837, and in a later edition introduced a chemical classification that is still the standard. X-ray diffraction was demonstrated by Max von Laue in 1912, and developed into a tool for analyzing the crystal structure of minerals by the father/son team of William Henry Bragg and William Lawrence Bragg . More recently, driven by advances in experimental technique (such as neutron diffraction ) and available computational power,

220-468: A sclerometer ; compared to the absolute scale, the Mohs scale is nonlinear. Tenacity refers to the way a mineral behaves, when it is broken, crushed, bent or torn. A mineral can be brittle , malleable , sectile , ductile , flexible or elastic . An important influence on tenacity is the type of chemical bond ( e.g., ionic or metallic ). Of the other measures of mechanical cohesion, cleavage

275-496: A mostly clear, colorless salt solution with little solid thermonatrite . The mineral natron is often found in association with thermonatrite , nahcolite , trona , halite , mirabilite , gaylussite , gypsum , and calcite . Most industrially produced sodium carbonate is soda ash (sodium carbonate anhydrate Na 2 CO 3 ) which is obtained by calcination (dry heating at temperatures of 150 to 200 °C) of sodium bicarbonate, sodium carbonate monohydrate, or trona . Geologically,

330-449: A much smaller sample) has essentially the same relationship. This implies that, given the chemical composition of the planet, one could predict the more common minerals. However, the distribution has a long tail , with 34% of the minerals having been found at only one or two locations. The model predicts that thousands more mineral species may await discovery or have formed and then been lost to erosion, burial or other processes. This implies

385-459: A polarizing microscope to observe. When light passes from air or a vacuum into a transparent crystal, some of it is reflected at the surface and some refracted . The latter is a bending of the light path that occurs because the speed of light changes as it goes into the crystal; Snell's law relates the bending angle to the Refractive index , the ratio of speed in a vacuum to speed in

440-836: A role of chance in the formation of rare minerals occur. In another use of big data sets, network theory was applied to a dataset of carbon minerals, revealing new patterns in their diversity and distribution. The analysis can show which minerals tend to coexist and what conditions (geological, physical, chemical and biological) are associated with them. This information can be used to predict where to look for new deposits and even new mineral species. Minerals are essential to various needs within human society, such as minerals used as ores for essential components of metal products used in various commodities and machinery , essential components to building materials such as limestone , marble , granite , gravel , glass , plaster , cement , etc. Minerals are also used in fertilizers to enrich

495-471: Is sodium bicarbonate , natron's other key ingredient. Natron is also the mineralogical name for the compound sodium carbonate decahydrate (Na 2 CO 3 · 10H 2 O), which is the main component in historical natron. Sodium carbonate decahydrate has a specific gravity of 1.42 to 1.47 and a Mohs hardness of 1. It crystallizes in the monoclinic -domatic crystal system , typically forming efflorescences and encrustations. The term hydrated sodium carbonate

550-460: Is an abbreviation of that element's Neo-Latin name natrium , which was derived from natron . The name of the chemical element Nitrogen is also a cognate to natron, it derives from Greek nitron and -gen ( a producer of something, in this case Nitric acid , which was produced from niter (potassium nitrate)). Niter was also an obsolete name for natron because in earlier times, both minerals used to be confused with each other. Historical natron

605-727: Is commonly used to encompass the monohydrate (Na 2 CO 3 · H 2 O), the decahydrate and the heptahydrate (Na 2 CO 3 · 7H 2 O), but is often used in industry to refer to the decahydrate only. Both the hepta- and the decahydrate effloresce (lose water) in dry air and are partially transformed into the monohydrate thermonatrite Na 2 CO 3 · H 2 O. Sodium carbonate decahydrate is stable at room temperature but recrystallizes at only 32 °C (90 °F) to sodium carbonate heptahydrate, Na 2 CO 3 · 7H 2 O, then above 37–38 °C (99–100 °F) to sodium carbonate monohydrate, Na 2 CO 3 · H 2 O. This recrystallization from decahydrate to monohydrate releases much crystal water in

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660-530: Is determined by comparison with other minerals. In the Mohs scale , a standard set of minerals are numbered in order of increasing hardness from 1 (talc) to 10 (diamond). A harder mineral will scratch a softer, so an unknown mineral can be placed in this scale, by which minerals; it scratches and which scratch it. A few minerals such as calcite and kyanite have a hardness that depends significantly on direction. Hardness can also be measured on an absolute scale using

715-810: Is found at Owens Lake and Searles Lake , California ; the Green River Formation of Wyoming and Utah ; the Makgadikgadi Pans in Botswana and in the Nile Valley in Egypt . The trona near Green River, Wyoming , is the largest known deposit in the world and lies in layered evaporite deposits below ground, where the trona was deposited in a lake during the Paleogene Period. Trona has also been mined at Lake Magadi in

770-454: Is similar to wet chemistry in that the sample must still be dissolved, but it is much faster and cheaper. The solution is vaporized and its absorption spectrum is measured in the visible and ultraviolet range. Other techniques are X-ray fluorescence , electron microprobe analysis atom probe tomography and optical emission spectrography . In addition to macroscopic properties such as colour or lustre, minerals have properties that require

825-435: Is so high, that little bicarbonate is present in solution (see reaction scheme above) – in which case the maximum temperature is increased to about 30 °C (86 °F). In most cases the mineral natron will form together with some amount of nahcolite ( sodium bicarbonate ), resulting in salt mixtures like the historical natron. Otherwise, the minerals trona or thermonatrite and nahcolite are commonly formed. As

880-399: Is the arrangement of atoms in a crystal. It is represented by a lattice of points which repeats a basic pattern, called a unit cell , in three dimensions. The lattice can be characterized by its symmetries and by the dimensions of the unit cell. These dimensions are represented by three Miller indices . The lattice remains unchanged by certain symmetry operations about any given point in

935-594: Is the identification and classification of minerals by their properties. Historically, mineralogy was heavily concerned with taxonomy of the rock-forming minerals. In 1959, the International Mineralogical Association formed the Commission of New Minerals and Mineral Names to rationalize the nomenclature and regulate the introduction of new names. In July 2006, it was merged with the Commission on Classification of Minerals to form

990-432: Is the tendency to break along certain crystallographic planes. It is described by the quality ( e.g. , perfect or fair) and the orientation of the plane in crystallographic nomenclature. Parting is the tendency to break along planes of weakness due to pressure, twinning or exsolution . Where these two kinds of break do not occur, fracture is a less orderly form that may be conchoidal (having smooth curves resembling

1045-481: Is viewed, it appears dark because it does not change the polarization of the light. However, when it is immersed in a calibrated liquid with a lower index of refraction and the microscope is thrown out of focus, a bright line called a Becke line appears around the perimeter of the crystal. By observing the presence or absence of such lines in liquids with different indices, the index of the crystal can be estimated, usually to within ± 0.003 . Systematic mineralogy

1100-460: Is white to colourless when pure, varying to gray or yellow with impurities. Natron deposits are sometimes found in saline lake beds which arose in arid environments. Throughout history natron has had many practical applications that continue today in the wide range of modern uses of its constituent mineral components. In modern mineralogy the term natron has come to mean only the sodium carbonate decahydrate (hydrated soda ash) that makes up most of

1155-846: The Kenyan Rift Valley for nearly 100 years. The northern part of Lake Natron is covered by a 1.5 m thick trona bed, and occurs in 'salt' pans in the Etosha National Park in Namibia . The Beypazari region in the Ankara Province of Turkey has some 33 trona beds in two fault -bound lensoid bodies in and above oil shales of the Lower Hirka Formation (16 in the lower and 17 in the upper body). The Wucheng basin trona mine, Henan Province China has some 36 trona beds (693–974 m deep),

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1210-457: The crowd-sourced site Mindat.org , which has over 690,000 mineral-locality pairs, with the official IMA list of approved minerals and age data from geological publications. This database makes it possible to apply statistics to answer new questions, an approach that has been called mineral ecology . One such question is how much of mineral evolution is deterministic and how much the result of chance . Some factors are deterministic, such as

1265-476: The microscopic study of rock sections with the invention of the microscope in the 17th century. Nicholas Steno first observed the law of constancy of interfacial angles (also known as the first law of crystallography) in quartz crystals in 1669. This was later generalized and established experimentally by Jean-Baptiste L. Romé de l'Islee in 1783. René Just Haüy , the "father of modern crystallography", showed that crystals are periodic and established that

1320-712: The sḥ-ntr- chapels. One pellet of natron. That which Horus spits out is smin . One pellet of natron. That which Set spits out is smin . One pellet of natron. That which the two harmonious gods (spit out) is smin . One pellet of natron. To say four times: Thou hast purified thyself with natron, together with Horus (and) the Followers of Horus. Five pellets of natron from Nekheb, Upper Egypt. Thou purifiest (thyself); Horus purifies (himself). One pellet of natron. Thou purifiest (thyself); Set purifies (himself). One pellet of natron. Thou purifiest (thyself); Thot purifies (himself). One pellet of natron. Thou purifiest (thyself);

1375-556: The Commission on New Minerals, Nomenclature, and Classification. There are over 6,000 named and unnamed minerals, and about 100 are discovered each year. The Manual of Mineralogy places minerals in the following classes: native elements , sulfides , sulfosalts , oxides and hydroxides , halides , carbonates, nitrates and borates , sulfates, chromates, molybdates and tungstates , phosphates, arsenates and vanadates , and silicates . The environments of mineral formation and growth are highly varied, ranging from slow crystallization at

1430-457: The Nature of Rocks , 1546) which began the scientific approach to the subject. Systematic scientific studies of minerals and rocks developed in post- Renaissance Europe. The modern study of mineralogy was founded on the principles of crystallography (the origins of geometric crystallography, itself, can be traced back to the mineralogy practiced in the eighteenth and nineteenth centuries) and to

1485-614: The Romans and others at least until AD 640. The mineral was also employed as a flux to solder precious metals together. Most of natron's uses both in the home and by industry were gradually replaced with closely related sodium compounds and minerals. Natron's detergent properties are now commercially supplied by soda ash (pure sodium carbonate), the mixture's chief compound ingredient, along with other chemicals. Soda ash also replaced natron in glass-making . Some of its ancient household roles are also now filled by ordinary baking soda , which

1540-652: The ancient Greco-Roman world, ancient and medieval China , and Sanskrit texts from ancient India and the ancient Islamic world. Books on the subject included the Natural History of Pliny the Elder , which not only described many different minerals but also explained many of their properties, and Kitab al Jawahir (Book of Precious Stones) by Persian scientist Al-Biruni . The German Renaissance specialist Georgius Agricola wrote works such as De re metallica ( On Metals , 1556) and De Natura Fossilium ( On

1595-450: The chemical nature of a mineral and conditions for its stability ; but mineralogy can also be affected by the processes that determine a planet's composition. In a 2015 paper, Robert Hazen and others analyzed the number of minerals involving each element as a function of its abundance. They found that Earth, with over 4800 known minerals and 72 elements, has a power law relationship. The Moon, with only 63 minerals and 24 elements (based on

1650-721: The connection between atomic-scale phenomena and macroscopic properties, the mineral sciences (as they are now commonly known) display perhaps more of an overlap with materials science than any other discipline. An initial step in identifying a mineral is to examine its physical properties, many of which can be measured on a hand sample. These can be classified into density (often given as specific gravity ); measures of mechanical cohesion ( hardness , tenacity , cleavage , fracture , parting ); macroscopic visual properties ( luster , color, streak , luminescence , diaphaneity ); magnetic and electric properties; radioactivity and solubility in hydrogen chloride ( H Cl ). Hardness

1705-566: The crystal structures of minerals. X-rays have wavelengths that are the same order of magnitude as the distances between atoms. Diffraction , the constructive and destructive interference between waves scattered at different atoms, leads to distinctive patterns of high and low intensity that depend on the geometry of the crystal. In a sample that is ground to a powder, the X-rays sample a random distribution of all crystal orientations. Powder diffraction can distinguish between minerals that may appear

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1760-416: The crystal. Crystals whose point symmetry group falls in the cubic system are isotropic : the index does not depend on direction. All other crystals are anisotropic : light passing through them is broken up into two plane polarized rays that travel at different speeds and refract at different angles. A polarizing microscope is similar to an ordinary microscope, but it has two plane-polarized filters,

1815-424: The evaporation of a salt lake will occur over geological time spans, during which also part or all of the salt beds might redissolve and recrystallize, deposits of sodium carbonate can be composed of layers of all these minerals. The following list may include geographical sources of either natron or other hydrated sodium carbonate minerals: Mineralogy Mineralogy is a subject of geology specializing in

1870-480: The field has made great advances in the understanding of the relationship between the atomic-scale structure of minerals and their function; in nature, prominent examples would be accurate measurement and prediction of the elastic properties of minerals, which has led to new insight into seismological behaviour of rocks and depth-related discontinuities in seismograms of the Earth's mantle . To this end, in their focus on

1925-564: The god purifies (himself). One pellet of natron. Thou also purifiest (thyself)—thou who art among them. One pellet of natron. Thy mouth is the mouth of a sucking calf on the day of his birth. Five pellets of natron of the North, Wadi Natrûn ( št-p.t ) Natron is an ingredient for making a distinct color called Egyptian blue , and also as the flux in Egyptian faience . It was used along with sand and lime in ceramic and glass-making by

1980-625: The growth of agricultural crops. Mineral collecting is also a recreational study and collection hobby , with clubs and societies representing the field. Museums, such as the Smithsonian National Museum of Natural History Hall of Geology, Gems, and Minerals , the Natural History Museum of Los Angeles County , the Carnegie Museum of Natural History , the Natural History Museum, London , and

2035-694: The high temperatures and pressures of igneous melts deep within the Earth's crust to the low temperature precipitation from a saline brine at the Earth's surface. Various possible methods of formation include: Biomineralogy is a cross-over field between mineralogy, paleontology and biology . It is the study of how plants and animals stabilize minerals under biological control, and the sequencing of mineral replacement of those minerals after deposition. It uses techniques from chemical mineralogy, especially isotopic studies, to determine such things as growth forms in living plants and animals as well as things like

2090-599: The historical salt. The English and German word natron is a French cognate derived through the Spanish natrón from Latin natrium and Greek nitron ( νίτρον ). This derives from the Ancient Egyptian word nṯrj . Natron refers to Wadi El Natrun or Natron Valley in Egypt, from which natron was mined by the ancient Egyptians for use in burial rites. The modern chemical symbol for sodium , Na ,

2145-403: The hydrogen atom in the symmetric (HC 2 O 6 ) anion is disordered. The environment of the disordered H atom was later investigated by Choi and Mighell (1982) at 300 K with three-dimensional single-crystal neutron diffraction: they concluded that the H atom is dynamically disordered between two equivalent sites, separated from one another by 0.211(9) Å. The dynamically disordered H atom

2200-529: The interior of a shell), fibrous , splintery , hackly (jagged with sharp edges), or uneven . If the mineral is well crystallized, it will also have a distinctive crystal habit (for example, hexagonal, columnar, botryoidal ) that reflects the crystal structure or internal arrangement of atoms. It is also affected by crystal defects and twinning . Many crystals are polymorphic , having more than one possible crystal structure depending on factors such as pressure and temperature. The crystal structure

2255-422: The latter of which has enabled extremely accurate atomic-scale simulations of the behaviour of crystals, the science has branched out to consider more general problems in the fields of inorganic chemistry and solid-state physics . It, however, retains a focus on the crystal structures commonly encountered in rock-forming minerals (such as the perovskites , clay minerals and framework silicates ). In particular,

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2310-540: The lattice: reflection , rotation , inversion , and rotary inversion , a combination of rotation and reflection. Together, they make up a mathematical object called a crystallographic point group or crystal class . There are 32 possible crystal classes. In addition, there are operations that displace all the points: translation , screw axis , and glide plane . In combination with the point symmetries, they form 230 possible space groups . Most geology departments have X-ray powder diffraction equipment to analyze

2365-399: The limited temperature stability of this compound and due to the fact that the absorption of carbon dioxide usually produces mixtures of bicarbonate and carbonate in solution. From such mixtures, the mineral natron (and also the historical one) will be formed only if the brine temperature during evaporation is maximally about 20 °C (68 °F) – or the alkalinity of the lake

2420-525: The lower 15 beds are 0.5–1.5 m thick, thickest 2.38 m; the upper 21 beds are 1–3 m thick, with a maximum of 4.56 m hosted and underlain by dolomitic oil shales of the Wulidui Formation. Trona has also been found in magmatic environments. Research has shown that trona can be formed by auto metasomatic reactions of late-magmatic fluids or melts (or supercritical fluid -melt mixtures), with earlier crystallized rocks within

2475-427: The mineral natron as well as the historical natron are formed as transpiro- evaporite minerals, i.e. crystallizing during the drying up of salt lakes rich in sodium carbonate. The sodium carbonate is usually formed by absorption of carbon dioxide from the atmosphere by a highly alkaline, sodium-rich lake brine , according to the following reaction scheme: Pure deposits of sodium carbonate decahydrate are rare, due to

2530-594: The orientations of crystal faces can be expressed in terms of rational numbers, as later encoded in the Miller indices. In 1814, Jöns Jacob Berzelius introduced a classification of minerals based on their chemistry rather than their crystal structure. William Nicol developed the Nicol prism , which polarizes light, in 1827–1828 while studying fossilized wood; Henry Clifton Sorby showed that thin sections of minerals could be identified by their optical properties using

2585-440: The original mineral content of fossils. A new approach to mineralogy called mineral evolution explores the co-evolution of the geosphere and biosphere, including the role of minerals in the origin of life and processes as mineral-catalyzed organic synthesis and the selective adsorption of organic molecules on mineral surfaces. In 2011, several researchers began to develop a Mineral Evolution Database. This database integrates

2640-488: The same plutonic complex, or by large-scale vapor unmixing in the very final stages of magmatism. The crystal structure of trona was first determined by Brown et al. (1949). The structure consists of units of 3 edge-sharing sodium polyhedra (a central octahedron flanked by septahedra), cross-linked by carbonate groups and hydrogen bonds . Bacon and Curry (1956) refined the structure determination using two-dimensional single-crystal neutron diffraction , and suggested that

2695-706: The same in a hand sample, for example quartz and its polymorphs tridymite and cristobalite . Isomorphous minerals of different compositions have similar powder diffraction patterns, the main difference being in spacing and intensity of lines. For example, the Na Cl ( halite ) crystal structure is space group Fm3m ; this structure is shared by sylvite ( K Cl ), periclase ( Mg O ), bunsenite ( Ni O ), galena ( Pb S ), alabandite ( Mn S ), chlorargyrite ( Ag Cl ), and osbornite ( Ti N ). A few minerals are chemical elements , including sulfur , copper , silver , and gold , but

2750-421: 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. Early writing on mineralogy, especially on gemstones , comes from ancient Babylonia ,

2805-425: The vast majority are compounds . The classical method for identifying composition is wet chemical analysis , which involves dissolving a mineral in an acid such as hydrochloric acid (HCl). The elements in solution are then identified using colorimetry , volumetric analysis or gravimetric analysis . Since 1960, most chemistry analysis is done using instruments. One of these, atomic absorption spectroscopy ,

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2860-413: Was also an ancient household insecticide, and was used for making leather as well as a bleach for clothing. The mineral was used during mummification ceremonies in ancient Egypt because it absorbs water and behaves as a drying agent. Moreover, when exposed to moisture, the carbonate in natron increases pH (raises alkalinity ), which creates a hostile environment for bacteria. In some cultures, natron

2915-474: Was harvested directly as a salt mixture from dry lake beds in ancient Egypt , and has been used for thousands of years as a cleaning product for both the home and body. Blended with oil, it was an early form of soap . It softens water while removing oil and grease. Undiluted, natron was a cleanser for the teeth and an early mouthwash . The mineral was mixed into early antiseptics for wounds and minor cuts. Natron can be used to dry and preserve fish and meat. It

2970-433: Was reinvestigated at low temperature by O'Bannon et al. 2014 and they concluded that it does not order at temperatures as low as 100K. Natron Natron is a naturally occurring mixture of sodium carbonate decahydrate ( Na 2 CO 3 ·10H 2 O, a kind of soda ash ) and around 17% sodium bicarbonate (also called baking soda, NaHCO 3 ) along with small quantities of sodium chloride and sodium sulfate . Natron

3025-589: Was thought to enhance spiritual safety for both the living and the dead. Natron was added to castor oil to make a smokeless fuel , which allowed Egyptian artisans to paint elaborate artworks inside ancient tombs without staining them with soot. The Pyramid Texts describe how natron pellets were used as funerary offerings in the rites for the deceased pharaoh, "N". The ceremony required two kinds of natron, one sourced from northern (Lower) and one from southern (Upper) Egypt. Smin , smin opens thy mouth. One pellet of natron. O N., thou shalt taste its taste in front of

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