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Beryl

Beryl (/ ˈ b ɛr əl / BERR-əl) is a mineral composed of beryllium aluminium silicate with the chemical formula Be 3 Al 2 Si 6 O 18. 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, …

Cobalt

Cobalt is a chemical element with the symbol Co and atomic number 27. As with nickel, cobalt is found in the Earth's crust only in a chemically combined form, save for small deposits found in alloys of natural meteoric iron.The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal.. Cobalt-based blue pigments …

Mineral

A rock is an aggregate of one or more minerals or mineraloids. Some rocks, such as limestone or quartzite, are composed primarily of one mineral – calcite or aragonite in the case of limestone, and quartz in the latter case. Other rocks can be defined by relative abundances of key (essential) minerals; a granite is defined by proportions of quartz, …

Apatite: The mineral apatite information and pictures

Apatite is essential in the manufacture of phosphate fertilizers, and is very important in the chemical and pharmaceutical industries. Apatite is also a popular collectors mineral, and some transparent specimens are faceted for collectors. The gemmy violet and reddish forms are very much valued by collectors and command high prices.

Microsoft takes the gloves off as it battles Sony for its …

Microsoft pleaded for its deal on the day of the Phase 2 decision last month, but now the gloves are well and truly off. Microsoft describes the CMA's concerns as "misplaced" and says that ...

The Mineral and Gemstone Kingdom: Home

An interactive reference guide to rocks, minerals, and gemstones. The Mineral and Gemstone Kingdom is a free informational and educational guide to rocks, minerals, gemstones, and jewelry. This site has been providing detailed information and photos of hundreds of mineral and gemstone since 1997 and is one of the leading education …

Could Call of Duty doom the Activision Blizzard deal?

Hello, and welcome to Protocol Entertainment, your guide to the business of the gaming and media industries. This Friday, we're taking a look at Microsoft and Sony's increasingly bitter feud over Call of Duty and whether U.K. regulators are leaning toward torpedoing the Activision Blizzard deal.

Fool's Gold and Real Gold

It has a lower hardness than pyrite (3.5 to 4) and a lower specific gravity than pyrite (4.1 to 4.3), but the same tests can separate chalcopyrite from gold. Chalcopyrite also has a greenish black streak. Pyrrhotite is an iron sulfide mineral with a chemical composition of Fe (x-1) S. It has a high specific gravity, often has a brassy color ...

Carbon disulfide

Carbon disulfide (also spelled as carbon disulphide) is a neurotoxic, colorless, volatile liquid with the formula CS 2 and structure S=C=S.The compound is used frequently as a building block in organic chemistry as well as an industrial and chemical non-polar solvent.It has an "ether-like" odor, but commercial samples are typically contaminated …

Compound vs Mixture

A compound is represented using its chemical formula that represents the symbols of its constituent elements and the number of atoms of each element in one molecule of the compound. ... Compounds have specific mass ratios. e.g. pyrite has 46.6% iron and 53.4% sulphur by mass. This is true of all pyrite no matter the sample size.

Scaly-foot gastropod

Chrysomallon squamiferum, commonly known as the scaly-foot gastropod, scaly-foot snail, sea pangolin, or volcano snail is a species of deep-sea hydrothermal-vent snail, a marine gastropod mollusc in the family Peltospiridae. C. squamiferum differs greatly from other deep-sea gastropods, even the closely related neomphalines. In 2019, it was …

Givenchy official site

Discover all the collections by Givenchy for women, men & kids and browse the maison's history and heritage

Pyrrhotite: Physical properties, uses, composition

Magnetic Properties of Pyrrhotite. Pyrrhotite is similar to another iron sulfide mineral named troilite. Troilite has a chemical composition of FeS, while pyrrhotite's chemical composition is Fe (1-x) S. Pyrrhotite is deficient in iron because some of the iron sites in its crystal lattice are vacant (empty). That is why the iron in the formula has a subscript of 1-x.

Sulfur

Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic.Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formula S 8.Elemental sulfur is a bright yellow, crystalline solid at room temperature. Sulfur is the tenth most abundant …

About Our Coalition

About Our Coalition. Prop 30 is supported by a coalition including CalFire Firefighters, the American Lung Association, environmental organizations, electrical workers and businesses that want to improve California's air quality by fighting and preventing wildfires and reducing air pollution from vehicles.

Hematite

Hematite (/ ˈ h iː m ə ˌ t aɪ t, ˈ h ɛ m ə-/), also spelled as haematite, is a common iron oxide compound with the formula, Fe 2 O 3 and is widely found in rocks and soils. Hematite crystals belong to the rhombohedral lattice system which is designated the alpha polymorph of Fe 2 O 3.It has the same crystal structure as corundum (Al 2 O 3) …

Aluminium sulfate

Aluminium sulfate is a salt with the formula Al 2 (SO 4) 3.It is soluble in water and is mainly used as a coagulating agent (promoting particle collision by neutralizing charge) in the purification of drinking water and wastewater treatment plants, and also in paper manufacturing.. The anhydrous form occurs naturally as a rare mineral …

Chemical Properties of Minerals

Hydrous Minerals. Minerals containing water in their structure are known as hydrous minerals. The hydrous mineral Gypsum has a chemical formula of "CaSO 4 · 2H 2 O". The large number 2 in front of the H 2 O signifies that there are two water (H 2 O) molecules for every molecule of CaSO 4.The dot in between CaSO 4 and 2H 2 O indicates that these …

Lime sulfur

The exact chemical reaction leading to the synthesis of lime sulfur is poorly known and is generally written as: Ca(OH) 2 + x S → CaS x + by products (S 2 O 2− 3, SO 2− 3, SO 2− 4) where x = 2–8 and x value is often found around 5, calcium pentasulfide, a polysulfide. as reported in a document of the US Department of Agriculture (USDA).

Glossary of chemical formulae

This is a list of common chemical compounds with chemical formulae and CAS numbers, indexed by formula.This complements alternative listing at list of inorganic compounds.There is no complete list of chemical compounds since by nature the list would be infinite. Note: There are elements for which spellings may differ, such as …

DePaul University | DePaul University, Chicago

Our Commitment to Anti-Discrimination. DePaul University does not discriminate on the basis of race, color, ethnicity, religion, , gender, gender identity, sexual orientation, national origin, age, marital status, pregnancy, parental status, family relationship status, physical or mental disability, military status, genetic information or other status protected …

Uranium ore

Uranium is a silvery-gray metallic weakly radioactive chemical element.It has the chemical symbol U and atomic number 92. The most common isotopes in natural uranium are 238 U (99.27%) and 235 U (0.72%). All uranium isotopes present in natural uranium are radioactive and fissionable, and 235 U is fissile (will support a neutron …

Alkali soil

Alkali, or Alkaline, soils are clay soils with high pH (greater than 8.5), a poor soil structure and a low infiltration capacity. Often they have a hard calcareous layer at 0.5 to 1 metre depth. Alkali soils owe their unfavorable physico-chemical properties mainly to the dominating presence of sodium carbonate, which causes the soil to swell and difficult to …

Cellular respiration

Cellular respiration is the process by which biological fuels are oxidised in the presence of an inorganic electron acceptor such as oxygen to produce large amounts of energy, to drive the bulk production of ATP. Cellular respiration may be described as a set of metabolic reactions and processes that take place in the cells of organisms to convert …

The "Acid Test" for Carbonate Minerals and Carbonate …

The Acid Test on Rocks. LIMESTONE, DOLOSTONE, AND MARBLE. Some rocks contain carbonate minerals, and the acid test can be used to help identify them. Limestone is composed almost entirely of calcite and will produce a vigorous fizz with a drop of hydrochloric acid. Dolostone is a rock composed of almost entirely of dolomite. It will …

Chalcogenide

A chalcogenide is a chemical compound consisting of at least one chalcogen anion and at least one more electropositive element. Although all group 16 elements of the periodic table are defined as chalcogens, the term chalcogenide is more commonly reserved for sulfides, selenides, tellurides, and polonides, rather than oxides. Many metal ores …

Pyrite

The mineral pyrite (/ˈpaɪraɪt/),[6] or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula FeS2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral. Pyrite cubic crystals on marl from Navajún, La Rioja, Spain (size: 95 by 78 millimetres [3.7 by 3.1 in], 512 grams [18.1 oz]; main crystal: 31 ...

Sulfide mineral | Definition, Examples, Identification, & Facts

The composition of the sulfide minerals can be expressed with the general chemical formula AmSn, in which A is a metal, S is sulfur, and m and n are integers, giving A2S, AS, A3S4 and AS2 stoichiometries. Browse Search. ... The covalent property of sulfur allows sulfur-sulfur bonds and the incorporation of S 2 pairs in some sulfides such as pyrite.

Calcite: Meaning, Properties and Powers

Calcite is a rock-forming mineral with a chemical formula of CaCO3. It is widespread and found throughout the world in sedimentary, metamorphic, and igneous rocks. Some geologists consider it to be a "ubiquitous mineral" – one that is found everywhere. Calcite is classed as a carbonate and has a vitreous or glassy luster.

Twinning, Polymorphism, Polytypism, Pseudomorphism

Pericline Law - The pericline law has [010] as the twin axis. As stated above, pericline twinning occurs as the result of monoclinic orthoclase or sanidine transforming to microcline (all have the same chemical formula - KAlSi 3 O 8). Pericline twinning usually occurs in combination with albite twinning in microcline, but is only observable ...

Disulfide

Thiolates, not thiols, attack disulfide bonds. Hence, thiol–disulfide exchange is inhibited at low pH (typically, below 8) where the protonated thiol form is favored relative to the deprotonated thiolate form. (The pK a of a typical thiol group is roughly 8.3, but can vary due to its environment.). Thiol–disulfide exchange is the principal reaction by which …

Calcite

Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (CaCO 3).It is a very common mineral, particularly as a component of limestone.Calcite defines hardness 3 on the Mohs scale of mineral hardness, based on scratch hardness comparison.Large calcite crystals are used in optical equipment, and …

Mineral Varieties and Other Names A-Z

Complete index of minerals varieties and other names.

Sulfuric acid

Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid (Commonwealth spelling), known in antiquity as oil of vil, is a mineral acid composed of the elements sulfur, oxygen and hydrogen, with the molecular formula H 2 SO 4.It is a colorless, odorless and viscous liquid that is miscible with water.. Pure sulfuric acid does …

Fluorite Meanings and Crystal Properties

Fluorite Meanings, Zodiacs, Planets, Elements, Colors, Chakras, and more. Science & Origin of FluoriteFluorite is a calcium crystal that crystallizes in the form of masses, cubic, and octahedral crystals. It was first referenced in 1530 due to its important aid in flux production. It's a commonly occurring mineral with a majority of veins and deposits in …

Abiogenesis

In 1952, Stanley Miller and Harold Urey carried out a chemical experiment to demonstrate how organic molecules could have formed spontaneously from inorganic precursors under prebiotic conditions like those posited by the Oparin-Haldane hypothesis. It used a highly reducing (lacking oxygen) mixture of gases—methane, ammonia, and …

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