Barite color

In the glass (qv) and ceramic industry (see Ceramics), barite can be used both as a flux, to promote melting at a lower temperature or to increase the production rate, and as an additive to increase the refractive index of glass. The viscosity of barite-containing glass often needs to be raised. Alumina in the form of feldspar is sometimes used. To offset any color produced by iron from the barite addition, more decolorizer may be needed. When properly used, barytes help reduce seed, increase toughness and brilliancy, and reduce annealing time. Barite is also a raw material for the manufacture of other barium chemicals. 

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 that is colorless is pure, but radiation damage centers commonly cause color. For example, 0 (in some blue crystals), SOJ (in some honey-yellow and blue crystals), and SO2 (in yellow crystals) centers have been identified in barite. 

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. 

BARYTOCALCITE. This mineral is a carbonate of barium and calcium il crystallizes in the monoclinic system but occurs massive as well. Il lias a perfect cleavage parallel to the prism and one, less perfect, parallel to the base fracture, sub-conchoidal brittle hardness, 4 specific gravity, 3.66-3.71 luster, vitreous color, white or gray or may be greenish or yellowish transparent to translucent. Barytocalcite is found in Cumberland. England, associated with barite and fluorite. 

Strontium, Barium Strontium was discovered near, and named after, the small town of Strontian, Scotland, in 1787. There are no commercial uses for the pure metal, but the carbonate salt, SrC03, is used in the manufacture of glass for color TV picture tubes. Barium is found principally in the minerals witherite (BaC03) and barite (BaSC ), after which it is named. Though water-soluble salts of barium are extremely toxic, barium sulfate is so insoluble that it is used in medicine as a contrast medium for stomach and intestinal X rays. Like strontium, barium metal has no commercial uses, but various compounds are used in glass manufacture and in drilling oil wells. 

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. 

Strontium, element number 38, has a density of 2.63 g/cm3 and is the 16th most abundant element on Earth. Barium, element number 56, has a density of 3.51 g/cm3 and ranks 14th in abundance. Both elements are silvery-colored metals. Because alkaline earths react so readily with any water in the environment to form ions and compounds, neither element would ever be found as the native metal. In all of their ores, they occur as +2 ions. The principal sources of the two elements are the minerals celestite (SrS04), strontianite (SrC03), and barite (BaS04). 

The snlfate, as permanent white, is also used in paint, in x-ray diagnostic work, and in glassmaking. Barite is extensively used as a weighing agent in oil-well drilling flnids, and is nsed in making rubber. The carbonate has been used as a rat poison, while the nitrate and chlorate give colors in pyrotechny. All barium compounds that are water- or acid-soluble are poisonous. 

Celestite [7759-02-6] (syiL, celestine) [from the Latm, caelestis, meaning celestial] (ICSD 28055 and PDF 5-593) SrSO, M= 183.6836 47.70 wt.% Sr 17.46 wt.%S 34.84 wt.% 0 Coordinence Sr(6), S(4) (Sulfetes, diromates, molybdates, and tungstates) Orthorhombic a = 835.9 pm b= 535.2 pm c= 686.6 pm (Z = 4) P.G. mmm S.G. P2,nma Barite type Biaxial (-t) a= 1.622 1.624 r= 1.631 S= 0.009 2y=5i Dispersion moderate 3-3.5 3970 Habit tabular, radiated fibrous, crystalline, massive, granular. Color colorless, bluish white, yellowish white, or reddish white. Diaphaneity transparent to translucent. Luster vitreous (ie., glassy). Streak white. Qeavage (001) perfect, (210) good. Fracture uneven to conchoidal, brittle. Chemical decomposed at 1607 C Occurrence sedimentary rocks. 

Barium is a silvery metal, highly reactive. Salts of the element impart a green color to flames. Barium metal has few practical applications but barium sulfate is widely used. It is opaque to X-rays and is used as an X-ray contrast medium. Finely ground barite, suspended in water, is pumped down into the bore holes during drilling for oil. It prevents blowouts. 

Drilling grade - Barite for well drilling fluids is typically a 200 mesh product with specific gravity of at least 4.2 (i.e., >90% BaS04 ). Color is not critical, but water-soluble alkaline earth metals are controlled so as not to interfere with drilling fluid rheology. 

Blanc fixe and finely ground barite are also used as extenders for water-based paints, particularly in wood paints requiring a high level of gloss and minimum color distortion. The high refractive index of these materials allow them to function as a translucent white pigment in latex paints, providing a... 

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