Take a look at some of the handpicked varieties of high quality slates and quartzite from our huge collection.
Read More About Slate & Quartzite :
Slates are dense and fine grained rock. The colour of slates are generally gray, red, brown and green ranging from dark to light. It is produced by the compression of clays, shale, and various other rocks developing a characteristic cleavage consisting sericite and quartz with biotite, chlorite, and hematite as principal accessories.
In other words slates are generally formed by low-grade regional metamorphism of pelithic sediments or fine-grained tuffs. It can be associated with other metamorphic sedimentary or volcanic rocks.
Slates are or argillaceous origin of metamorphic rocks and can also be defined as a layered stone. Fossils may be sometimes preserved in slate but are invariably distorted. Folds are often apparent in the field. Too fine-grained are tough to distinguished with the naked eye.
The parent rock for quartzite is quartz-rich sandstone. As sandstone becomes deeply buried, rising temperature will fuse the quartz grains together forming the extremely hard and weather-resistant rock quartzite. Like marble, quartzite comes in many colors, but when pure it is light-colored. Quartzite tends to have a sugary appearance, and when broken the fractures cut through the sand grains, not around them as with a sandstone.
Use of Slate & Quartzite :
- Slate is used as Stepping and Paving stone in garden
- Slate is also used in Picture frame, clocks, jewellery, mirrors, coasters, trivets, switch plates, candle holders.
- Square blocks for a break band in section of granite paving is made with slate stone.
- Quartzite is usually dyed to some pleasing color or otherwise fashioned into decorative items.
Physical Properties of Slate & Quartzite :
Physically Slates are Metamorphic-Argillaceous rocks, which has developed a well-marked splittable cleavages with or without developed recrystallization & spots/knots of minerals like garnet, pyrite, andulasite, etc. They are normally fine to medium grained, moderately hard & compact, less homogeneous with varying textures & shades. It has an ability to split into thin layers along the plane of cleavages due to flattened & elongated minerals along the plane of cleavage.
Quartzite on the other hand are very Hard, Compact, Fine grained, equi-granular homogeneous rocks of metamorphic nature.
|Hardness||3 to 4 on Moh’s Scale||6.5 to 7 on Moh’s Scale|
|Density||2.6 to 2.8 Kg/cm3||2.3 to 2.4 Kg/cm3|
|Compressive Strength||24 to 36 N/mm2||90 to 140 N/mm2|
|Modulus of Rupture||22 to 34 N/mm2||16 to 40 N/mm2|
|Water Absorption||1.5 to 2%||1.0 – 1.2 %|
|Porosity||Low to very low||Low to very low|
Chemical Properties of Slate & Quartzite :
Chemically Marbles are crystalline rocks composed predominantly of calcite, dolomite or serpentine minerals. The other minor constituents vary from origin to origin
|Alumina (Al2O3)||15 to 20%||1 to 1.5%|
|Soda (Na2O) & Potash (K2O)||2-4%||Less then 1%|
|Lime (CaO)||0.5-1%||Less then 0.5%|
|Magnesia (MgO)||0.5-3%||Less then 0.5%|
|Loss On Ignition (LOI)||3-4%||Less then 0.5%|