Premium Black Granite From Our Own Quarry
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Description: Premium Black Granite is a very dark black, fine to close-grained black basalt (dolerite) of the Precambrian period with equi-granular crystalline texture. This stone internationally may be nominated as a granite but in the area of application of the European Standard this stone must be nominated as a dolerite. A small sample of Premium Black granite is usually representative not having a wide variation in colour and veining however swatch samples must be approved for large projects to ensure that the blocks are all extracted from the same quarry face for matching purposes. During the polishing process a clear epoxy resin filler may be used to fill any micro fissures or tiny pitting however this does not affect the integrity of the stone, it merely provides an even smoother surface finish. Premium Black granite is suitable for both interior and exterior use futhermore is frost resistant and with a constant polish.
Premium Black granite is the darkest of the Warangal black granites, it is not so widely available plus it commands a higher price, be vigilant if offered this at a lower cost than other grades.
Black Granite Shades
As a generalisation most black granite quarries have varying shades of black. This variation in shading is completely natural and usually occurs with the ground level of the quarry being lighter with the deeper the granite is quarried becoming darker, however some quarries may vary in shade along its length or width. The experienced quarryman knows where the lighter and darker shades are and can supply to the customer's preferences. All of our Indian black granites are from the Deccan Plateau.
NOTE: It is a fact that some unscrupulous dealers will actually dye the lighter shades and try to sell them as the Ultimate Black, Premium Black or Absolute Black product at its correspondingly higher price, with totally normal usage these "doctored" blacks will lose their artificially applied darkness. To check for dying try the lemon juice or acetone test. Do ensure that the granite is washed clean before doing this otherwise it may simply be general dirt. Take a clean white rag and apply some lemon juice or acetone to the granite surface. If any residue or black appears on the rag then it has been dyed. Also, if you have several small sample choices, leave a drop of the lemon juice for five minutes on the polished surface, wipe the surface clean and observe the results, once again any dull spot or patch and the material has been doctored.
Needless to say we never use colour enhancers.
To assist all potential black granite purchasers we have produce an Absolute Black Granite Guide.
Products: Suitable for construction projects both commercial and domestic, prefabricated countertops/worktops, vanities, tiles, backsplashes, paving, fireplaces and memorials.
Premium Quality Slab Sizes 2 & 3cm
Standard Slab Sizes 2 & 3cm
Granite Countertops 2 & 3cm
Calibrated Tiles: Standard sizes available are:
305 x 305 x 10 mm (12" x 12" x 3/8")
More granite tile and production information.
Surface Finish: Premium Black granite looks best with a gloss polished surface but is also available as honed, leather/satin, river-washed/antique, thermal/flamed, brushed and sandblast finish. We never use colour enhancers.
Sealing: Test with a small sample. It is most unlikely that a sealant can be used on Premium Black granite due to the very tight grain formation, attempts at sealing it could actually create a residue film build-up.
Block Sizes: This is a very large black granite quarry, Premium Black Granite is quarried at the lowest levels and therefore much more difficult to extract, the lower the level in the pit the more difficult it is to extract owing to the lack of work space. Granite blocks suitable for gangsaw size down to economical tile-sized and monument blocks are available however there is always a big demand for these blocks therefore for larger projects it is extremely important to give us considerable advanced notice. Extraction commenced in the very early 70s. For commercial projects it is important to ensure that blocks are selected from the same quarry face, do not try and match-up with alternative black granite sources.
Rough blocks are usually exported by Break Bulk however intermodal containerisation is available at extra cost. Finished products are packed into sea-worthy wooden crates and loaded into containers.
Quarry Location: Premium Black granite is from our own sheet bedrock quarry near Warrangal, Andhra Pradesh, India.
Synonyms: BG A1, BG A2
Dolerite (Diabase, Microgabbro): A dark-coloured, medium-grained igneous rock which contains plagioclase feldspar of labradorite composition and pyroxene of augite or titanaugite composition as essential minerals, and magnetite, titano-magnetite, or ilmenite as accessory minerals. Where olivine also occurs as an additional mineral, the rock is termed an "olivine dolerite". Where quartz occurs as an additional mineral in the groundmass, the rock is termed a "quartz dolerite". Dolerites are the medium-grained equivalents of basalts and, like the basalts, can be divided into alkali and tholeiitic types. Dolerites are commonly found in shallow level intrusions such as dykes, sills, or plugs.
Mineral Composition: Average by %
Compressive Strength: 3011/kg cm2
After Freezing: 2636/kg cm2
Ultimate Tensile Strength: 280/kg cm2
Water Absorption: 0.00001
Volumetric Weight: 2989 kg/m3
Hardness (Moh's Scale): 6-7
Note: These figures and details are given for guidance purposes only, no reliance should be taken as to their accuracy.