Baryte from Maroc
Baryte is a Barium Sulfate from barite group.
Baryte is generaly white or colorless and the main source of barium.
The baryte group consists of Baryte, Celestina (strontium sulfate), Anglesite (lead sulfate) and anhydrite (calcium sulfate).
Baryte and Celestine form solid solution (Ba,Sr)SO4
Although baryte contains the toxic heavy metal barium, it is not toxic because barium sulfate is extremely insoluble in water.
The spelling is Barite in United States and Baryte in UK and other countries.
Some forms with brown color and sand inclusions, looking as a flower, also named Barite Desert Roses but it is not a Gypsum like Desert Rose .
Baryte often replaces other minerals and may even replace organic materials like wood, shells and fossils.
Primary forms of baryte group:
Baryte - (barium sulfate) BaSO4 [58,84% Barium; 13,74% Sulfur; 27,42% Oxygen]
Celestine - (strontium sulfate) SrSO4 [47,70% Strontium; 17,47% Sulfur; 34,84% Oxygen]
Anglesite - (lead sulfate) PbSO4 [68,32% Lead; 10,57% Sulfur; 21,10% Oxygen]
Anhydrite - (calcium sulfate) CaSO4 [29,44% Calcium; 23,55% Sulfur; 47,01% Oxygen]
Uses:
In oil and gas drilling used as a weighting agent for drilling fluids in oil and gas exploration to suppress high formation pressure and prevent blowouts.
Is used to drill petroleum.
Other uses include filler in paint and plastics, sound reduction in engine compartments, coat of automobile finishes for smoothness and corrosion resistance, friction products, radiation shielding cement, glass ceramics, medical application (barium for contrast CT scan).
It is also used to produce barium carbonate used for manufacturing LED glass for television and computer screens (historically in cathode ray tube) and for dielectrics.
Sometimes used as gemstone.
Is the main ore of element barium.
Strontium sulfate (Celestine) is used for its content (strontium) in fireworks and various metal alloy.
Characteristics for mineral Barite/Baryte - barium sulfate:
Category Sulfate mineral, barite group
Chemical formula: BaSO4
Variable formula (Ba,Sr)SO4
Crystal system: Orthorhombic
Color: colorless, yellow, white, red, pink, purple, brown, blue, green, gray, black, multicolor or manded
Streak white
Hardness 3-3,5
Crystal system Orthorhombic
Transparent to opaque
Luster Vitreous to pearly
Specific gravity 4,3-4,6
Density 4,48
Cleavage 1,1 basal; 2,1 prismatic; 3,1 pinacoidal
Fracture uneven
Tenacity brittle
Rock type: sedimentary, metamorphic
Special characteristics:
commonly fluorescent in a variety of colors; can have phosphorescence
Tests:
Heaviness, streak white, hardness 3-3,5
Fluorescence; Phosphorescence
Distinguishing similar minerals:
Celestine - very dificult by appearance, lighter in weight
Calcite - has perfect rhombohedral cleavage, lighter in weight, effervesces in hydrochloric acid
Fluorite - forms isometric crystals, lighter in weight
Feldspars - much harder, lighter in weight
Anglesite - has an adamantine luster
Luminescence:
Baryte - yellow white, bluish white in long wave and yellow white, bluish white, yellow, orange in short wave UV; intensity medium, frecuency often in long wave and rare in short wave
Activator: main Uranyl ion UO as impurities with peak at 501, 522, 544, 568 nm
Other activators: Pb blue spectrum; S; organic impurities; Cu; Eu 375, 613, 615, 697 nm; Ce 302, 305, 330, 360 nm; Tb 488, 544 nm; Ag peak at 635 nm; Nd 389, 446, 589, 672 nm; Bi 3 ion 426-430 and Bi 2 ion replacing Ba with peak at 625 nm
Celestine - fluorescent, short wave yellow, white blue and long wave yellow, white blue
Anglesite - yellow, white, orange, red in long wave and orange, yellow, white in short wave; activator Pb peak 475 nm
Anhydrite - pink, white, blue in long wave and red, white or blue in short wave; intensity weak; can have thermoluminescence; common activator Sm; other S, Eu, Ce, Eu, Dy, Tb, Mn, O, Nd, Yb
for more info on peak on Anhydrite press here
Varieties:
Celestine - bluish crystal and colorless in pure form, can have also a wider range of colors but usually blue.
Celestine is isomorphous with Baryte and may partially replace it. One specimen can be part Baryte part Celestine within a single crystal.
Is the principal source of strontium, commonly used in fireworks and various metal alloy.
Celestine crystals are found in some geodes.
Occurs as crystals in compact massive and fibrous forms, mostly in sedimentary rocks, often associated with gypsum, anhydrite and halite.
Chemical formula SrSO4
Composition Strontium sulfate and sometimes small amounts of barium
Color: blue, white, colorless, may be orange, brown, yellow, greenish blue, gray, multicolored
Streak white; Hardness 3-3,5
Density 3,9 - 4
Transparent to translucent
Can have fluorescence in short wave UV and may have thermoluminescence
Varieties: sand celestine - has sand inclusions causing specimens to be brown or grayish and opaque.
Common minerals: Calcite, Barite, Fluorite, Gypsum, Dolomite, Galena, Sphalerite, Strontianite, Pyrite, Colemanite, Halite, Sulfur
Distinguishing similar minerals:
Barite/Baryte - difficult, but Barite is heavier
Gypsum - softer, sectile, lighter
Calcite - perfect rhombohedral cleavage, lighter, effervescent in acid
Feldspars - harder, lighter in weight
Fluorite - forms only isometric crystals, lighter, has perfect cubic cleagave
Colemanite - harder, lighter in weight
Celestine from Russia
Anglesite - is a lead sulfate that occurs as an oxidation product of primary lead sulfide ore, Galena.
It contains 74% of lead by mass and has a high specific gravity of 6,3.
Is isomorphous with baryte and celestine.
Chemical formula PbSO4
Color: colorless to white, tinted gray, orange, yellow, green, blue, rarely violet
Crystal habit: granular, banded, nodular to stalactitic
Cleavage good, distinct
Fracture brittle
Hardness 2,5-3
Luster adamantine
Streak white
Specific gravity 6,3
Density 6,3
Common mineral association: Galena, Cerussite, Smithsonite, Hemimorphite, Sphalerite, Azurite, Malachite, Sulfur, Pyromorphite, Linarite
Distinguishing similar minerals:
Celestine - lacks adamantine luster, lighter in weight
Baryte/Barite - lacks adamantine luster
Cerussite - effervescent in hydrochloric acid, crystals frequently twinned
Phosgenite - may be difficult but occurs in different crystals, and is sectile and nonbrittle
Anhydrite - similar composition to gypsum but lacks water.
Transforms into gypsum by adding water.
Occurs in arid regions forming from dehydration of Gypsum.
It is used in the production of sulfuric acid and filler in paper.
Formula CaSO4
Hardness 3-3,5
Streak white
Specific gravity 2,9-3,0
Density 2,96-2,98
More info about Anhydrite in the hypsum post
Other names: Baritina baritina barityne baryte barite baritin baritinul heavy spar desert rose celestina celestin anglesit anglesitul celestinul anhydrit anhydritul anhidrit anhidritul
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