Minerals barite

Barium (eighteenth most abundant element) is also rather rare it occurs as the mineral barite, BaSCV... 

Kuroko deposits are characterized by large amounts of sulfate minerals (barite, anhydrite, and gypsum). Estimated total amount of barite and sekko (gypsum + anhydrite) from individual deposit is shown in Table 1.4. Sr contents of gypsum, anhydrite and barite... 

Alchemists in the early Middle Ages knew about some barium minerals. Smooth round pebble-like stones found in Bologna, Italy, were known as Bologna stones. When these odd stones were exposed to sunlight, or even a primitive reading lamp, they would continue to glow for several years. This characteristic made them attractive to witches as well as the alchemists. These stones are actually the mineral barite, barium sulfide (BaSO ), which today is a major source of barium metal. 

Its compounds have many practical uses. For example, when the mineral barite is ground up into a fine powder, it can be used as a filler and brightener for writing and computer paper. It is also used (along with zinc sulfide) as a pigment, called lithopone, for white paint. Barium compounds are also used in the manufacture of plastics, rubber, resins, ceramics, rocket fuel, fireworks, insecticides, and fungicides and to refine vegetable oils. 

Barium was discovered in 1808 by Sir Humphrey Davy. Its abundance in the earth s crust is about 0.0425% (425 mg/kg). The element also is found in sea water at trace concentration, 13 J,g/L. It occurs in the minerals barite or heavy spar (as sulfate) and witherite (as carbonate). 

Barium sulfate is widely distributed in nature and occurs as the mineral barite (also known as barytes or heavy spar). It often is associated with other metallic ores, such as fluorspar. Barites containing over 94% BaS04 can be processed economically. 

Soft crystalline solid rhombic crystal pure salt is white but color may vary the color of the mineral barite may vary among red, yellow, gray or green depending on impurities density 4.50 g/cm refractive index 1.64 melts around 1,580°C decomposes above 1,600°C hardness 4.3 to 4.6 Mohs insoluble in water (285 mg/L at 30°C) and alcohol Ksp 1.1 x 10-i° soluble in concentrated sulfuric acid. 

Barite is a barium sulfate, BaS04, with orthorhombic structure 2jm2jm2jm) where the sulfur is situated in tetrahedral coordination with oxygen, and barium in twelve-fold coordination with oxygen. The mineral barite is one of the first luminescent materials from which the famous Bologna stone was obtained. Nevertheless, up to today understanding of natural barite luminescence... 

Although the mineral (barite) in which this element was first recognized has a high specific gravity, the metal itself is very light. Edward Daniel Clarke objected therefore to the inappropriate name barium (meaning heavy) for this metal (105). The name persists nevertheless. 

BARITE. The mineral barite is barium sulfate, BaSOa crystallizing in the orthorhombic system. It may occur as tabular crystals, in groups, or lamellar, fibrous and massive, Barite has two perfect cleavages, basal and prismatic hardness, 3-3.5 specific gravity, 4.5, which has led to the term heavy spar, occasionally used for this mineral. Its luster is vitreous streak, white color, white to gray, yellowish, blue, red and brown transparent to opaque, it sometimes yields a fetid odor when broken or when pieces are rubbed togedier, due probably to the inclusion of carbonaceous matter. It is used as a source of barium compounds. 

Barium Minerals Barite (BaS04) and witherite (BaCOs) are commonly used to supply barium in ceramic formulations. Purified barium carbonate, made by dissolution and repredpitation, is used most frequently in ceramic processes and as fluxing compounds in the grazes, ass, and enamels of electronic ceramics and in heavy day products to prevent scumming. The use of these minerals have the drawback that upon heating they give off gas, which can cause cracks. 

Barium sulfate occurs in nature as the mineral barite. It can be prepared in the laboratory by precipitating a solution of blarium chloride with a soluble sulfate, such as sodium sulfate. By filtering oflE the precipitate and weighing it, a determination can be made either of the amount of barium in the original solution (an excess of sulfate being used), or of the amount of sulfate. 

Figure 2 Graph showing barium concentrations plotted versus the saturation index of the mineral barite calculated for Snake River Plain groundwater (source Wood and Low, 1988).

Derivation (1) By treating a solution of a barium salt with sodium sulfate (salt cake), (2) by-product in manufacture of hydrogen peroxide, (3) occurs in nature as the mineral barite (Arkansas, Missouri, Georgia, Nevada, Canada, Mexico). 

Barium sulfate, BaS04, occurs in the mineral barite (a). Calcium fluoride, Cap2, occurs in the mineral fluorite (b). Both are clear, colorless crystals. Minerals are often discolored by impurities. 

Ba barium, 56, 1808 named for the mineral barite, or heavy spar, in which it occurs from the Greek "barys ... 

Davy prepared barium by the same method. Minerals containing barium could be recognized by the green color their salts impart to flames. Because the mineral barite (BaS04) has a high density, the name barium, meaning heavy, was chosen for that element. 

Barium Sulfide, Black. Black ash. This is the crude barium sulfide obtained by strong heating of a mixture of barium sulfate mineral (barite) and charcoal. Contains... 

A second sedimentary component important for paleoceanographic reconstructions, which is prone to dissolution under conditions of sulfate reduction - or more precisely in srrlfate-depleted sediments - is the barium sulfate mineral, barite (BaSO ). Since a correlation has been detected between barite deposition and the flux of organic matter through the water column, the concentration of barite in sediments has been proposed and applied as a geochemical tracer to reconstruct past changes in ocean productivity (e.g.. Bishop... 

Fig. 8.10 Geochemical data for core GeoB 1023-4 recovered off north Angola (17°09.6 S, 10°59.9 E, 2047 m water depth). Barium and sulfate pore-water concentration profiles as well as the distribution of solid-phase barium indicate the precipitation of authigenic barite at a front slightly above the depth of complete sulfate consumption. Below the sulfate/methane transition barite becomes undersaturated and is thus subject to dissolution due to the total depletion of pore-water sulfate. Dissolved barium diffuses upwards into the sulfate zone where the mineral barite becomes supersaturated and so-called authigenic or diagenetic barite precipitates at a front at the base of the sulfate zone. Modified from Gingele et al. (1999), after Kolling (1991).

Inso in w. CA Registry No [7727-43-7]. Occurs in nature as the mineral barite, also as barytes and heavy spar. Prepn Is by adding sulfuric acid to the aq extract of BaS... 

Barium sulfates (barites, blanc fixe, heavy spar, permanent white, and terra ponder-osa) BaS04. n. A white powder obtained from the mineral barite or synthesized... 

Barium was first identified in the mineral barite by the Swedish chemist Scheele in 1774. The pure element was first prepared in 1808 by British chemist Sir Humphry Davy, who produced barium amalgam by electrolyzing an aqueous solution of barium chloride using a liquid-mercury cathode. After distilling mercury from the barium amalgam formed, he obtained pure barium metal. 

The metal barium has no significant use. Its principal compounds are barium sulfate, BaS04, which is only very slightly soluble in water and dilute acids, and barium chloride, BaCl2 2H20, which is soluble in water. Barium sulfate occurs in nature as the mineral barite. 

Most important mineral Barite (baryte) Witherite... 

Barium carbonate is the source of barium compounds. It is produced in an aqueous precipitation reaction from barium sulfide and sodium carbonate. (Barium sulfide is a soluble compound obtained by heating the mineral barite, which is barium sulfate, with carbon.) What are the molecular equation and net ionic equation for the precipitation reaction A solution containing 33.9 g of barium sulfide requires 21.2 g of sodium carbonate to react completely with it, and 15.6 g of sodium sulfide is produced in addition to whatever barium carbonate is obtained. How many grams of barium sulfide are required to produce 10.0 tons of barium carbonate (One ton equals 2000 pounds.)... 

Gaft M, Reisfeld R, Panczer G et al (2001) The nature of orange luminescence of mineral barite. Opt Mater 16(l-2) 279-290... 

Barium Sulfates n (barites, blanc fixe, heavy spar, permanent white, terra ponderosa) BaS04. A white powder obtained from the mineral barite or synthesized chemically. One of the synthetic varieties, hlanc fixe, is made by mixing aqueous solutions containing sulfate and barium ions. As a filler in plastics and rubbers, barium sulfate imparts opacity to X rays but only a low order of optical opacity. Thus it is useful as a filler when it is desired to increase specific gravity without adversely affecting the tinctorial power of pigments. (Ash M, Ash I (1998) Handbook of fillers, extenders and dilutents. Synapse Informtion Resources, Inc., New York). 

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