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Silica Sand
Introduction : Silica sand is produced by crushing sand stone or quartzite of open texture, and washing and grading it to yield requisite grain distribution. Silica flour is producted by crushing grinding and washing the high grade quartz, quartzite rocks or from white silica sand.
Chemical Composition : Sio2 the general impurities are iron/aluminium oxides and lime.
Physical Characters : Sandstone is a firable and hard.The grain size of the particles is variable. it is friable and mainly brown to grey in colour.
Specification : Glass making sand IS : 488 - 1963. Indian Standard for silica sand used for glass making.
Grades:
- Special Grade; intended for the manufacture of high grade colour less glass. Such as Crystal Glass, tableware and other decoratives wares.
- Grade 1. intended for the manufacture of decolourished glassware, such as container ware, lamp ware.
- Grade 2. intended for the manufacture of glassware where slight tint is permissible.
- Grade 3 intended for the manufacture of glasses like sheet glass and some colored glass like iron sulphur amber glass.
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Component
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Special grade
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Grade 1
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Grade 2
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Grade 3
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Silica(SIO2)% by wt.min
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99.00
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98.00
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97.50
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97.00
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II Iron Oxide
(as fe2 O3)% by wt.
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0.02
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0.04
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0.07
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0.12
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Titanium dioxide
(TiO2)% by wt.
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0.10
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0.10
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0.10
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0.10
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In foundries IS 1987-1947
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Grade
(Max)
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Silica%
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Alumina%
Iron
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Oxide%
(Max)
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Calcium (Max) Mg. Oxide%
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Alkalies%
(Max)
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A.
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Over 98
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1.0
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1.0
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1.0
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0.5
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B.
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Over 98
upto 95
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1.5
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1.0
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1.0
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0.5
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C.
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Over 95
up to 90
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5.0
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1.5
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2.0
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1.5
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Uses:
Silica sand used for water purification and manufacture of glass,synthetic foundary moulding catalysts, di-sodium ultramarine etc.it is also used for acid heat resistant ceramics, refractories, pottery glaze, enamed etc. Silica sand of 150 mesh is used in Sawing stone, grinding and surfacing glass and polishing marble Rounded Grains of silica sand are used for sand blasting it is also used as a filler in paints 'Wood Paste' moulded hard rubber goods, gypsum Plasters, oxychloride accoustic plasters and soap.
Geological Setting:
It occurs as loose or poorly consolidated deposits of sedimentary origin or as dunes blow inland from the coast or as accumulated deposits in estuaries
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