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Barite is the naturally occurring sulphate of barium (BaSO4). It is classified as an evaporite (salt) among industrial minerals. It is formed as a hydrothermal deposit in fissures and veins of highly compact sandstones and lateritic shale. Its formation is as a result of the metasomatic alteration and ionic exchange reactions in the crust resulting to the precipitation of this insoluble salt in the fissures and cracks of these highly baked sand stones and lateritic shale which usually serves as the host rock. In some cases the barite deposits are feruginised, that is, they contain appreciable quantity of iron thus making them look brownish and rusty. The depth of occurrence of these minerals ranges from 0.2m below the surface to over 12m. The specific gravity of barite ranges from 2.7 to 5.0 depending on the composition and depth of occurrence. The deep-seated deposits often have higher specific gravities than shallow deposits. However, in some mines, crystalline barite from shallow pits shows higher specific gravity than shallow deposits. However, in some mines, crystalline barite from shallow pits show higher specific gravity than deep seated samples collected. The exposure of shallow deposits to weathering/erosions and other agents of degradation often reduce the specific gravity. Also the presence of other gangue minerals like Ankerite, And siderite (the carbonates of iron) affects the specific gravity of barite. Barite occurrence is often associated with Lead/Zinc mineralization.

Barite commonly forms as large tubular crystals, as rosette-like aggregates of those crystals, or as divergent plates known as crested barite. Typically barite varies from colourless to white. It has specific gravity of between 3.6-4.5 which makes it suitable for use in drilling mud for the oil, gas and water drilling operations. Its unique specific gravity helps to carry rock cuttings to the surface and also to lubricate and cool the drilling bit. Its low oil absorption and wetability by oil allows barite to be used as filler and weighting agent.

For the oil and gas industry, the barite product specification is:

BaSO4 – 27.98%

AL2O3 – 0.1%

Specific Gravity – 4.2%

Barite density is 4.48, with a diaphaneity of transparent to translucent opaque.

Hardness is 3-3.5 calcite-copper penny.

Refractive index is 1.63.

Crystal structure is orthorhombic. Because if its extreme insolubility, it is not considered to be a toxic chemical.

Barite exploration involves stages ranging from reconnaissance survey, investigation of outcrops in road cuttings, old workings, stream and channel sampling to geophysical investigation. In areas where mineralized outcrops are identified, traverses are taken perpendicular to the strike of the outcrop at regular intervals. After determining the mineralized veins, test pits are sunk at 50 or 100 meters intervals to determine the extent of mineralization. Once mineralization is established, a trench is dug perpendicular to the trend of the vein to determine the thickness of the barite vein, and its lateral extent. The length of traverse to be taken depends on some factors including the length and interval between adjoining veins.
USES OF BARITE

There are many important uses of barite. Its application in the oil drilling industry accounts for about 75% of its use/ consumption. Barite is also used as a filler, extender, or weighting agent in products such as paints, plastics, and rubber. Some specific uses include its use in brake and clutch pads for automobiles, automobile paint primer for metal protection and gloss, and to add weight to rubber mudflaps on trucks and to the cement jacket around petroleum pipelines under water. In the metal casting industry, barite is part of the mold-release compounds. Because barite significantly blocks X-ray and gamma-ray emissions, it is used as aggregate in high-density concrete for radiation shielding around X-ray units in hospitals, nuclear powerplants, and university nuclear research facilities. Ultrapure barite consumed as liquid is used as a contrast medium in medical X-ray examinations. It is the raw material for barium chemicals, such as barium carbonate, which is an ingredient in faceplate glass in the cathode-ray tubes of televisions and computer monitors. Further use is in the making of expensive white pigment.

MARKET POTENTIAL

The economic significance of barite is indeed invaluable particularly in terms of its indispensability in the petroleum industry to date. The unique adaptable feature of barite mineral to the chemistry of the petroleum drilling and the notable role it plays is yet to be substituted by any other industrial mineral. Thus international market created by the oil and gas industry has been varying geometrically on a scale that is not difficult to predict.

The present day petroleum economics or trade line depicts both expandable application and higher market prices for the barite producing industry in the near future