Onsernone Granite From Switzerland
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Description: Onsernone granite is a fissionable, fine-grained, dark to medium grey gneiss (paragneiss) of the Carboniferous/Permian period. 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 gneiss. The veining and colour varies and a small sample of Onsernone granite may not be representative of the whole slab therefore 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. Onsernone Granite is suitable for both interior and exterior use futhermore is frost resistant and with a constant polish.
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: Onsernone 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.
Sealing: Test with a small sample. It is possible that a sealant can be used on Onsernone granite however excessive attempts at sealing it could actually create a residue film build-up.
Block Sizes: This is a quarry yielding selectable, grades of granite with blocks suitable for gangsaw size down to economical tile-sized blocks. For commercial projects it is important to ensure that blocks are selected from the same quarry face.
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: Onsernone granite is quarried 6 km behind Vergeletto, Val Vergeletto, Ticino, European Alps , Switzerland.
Synonyms: Onsernone Gneis, Onsernone-Gneis, Onsernone-Granit, Onsernonegranit, Onsornone, Sarizzo Onsernone, Vergeletto
Gneiss: A high grade metamorphic rock. Gneiss is medium to coarse-grained and may contain abundant quartz and feldspar, which some petrographers regard as essential components. The banding is usually due to the presence of differing proportions of minerals in the various bands; dark and light bands may alternate because of the separation of mafic (dark) and felsic (light) minerals. Banding can also be caused by differing grain sizes of the same minerals. The mineralogy of a particular gneiss is a result of the complex interaction of original rock composition, pressure and temperature of metamorphism, and the addition or loss of components.
Mineral Composition: Average by %
Compression Tensile Strength: 1720 kg/cm2
Tensile Strength After Freeze-Thaw Cycles: 1664 kg/cm2
Unitary Modulus Of Bending Tensile Strength: 139 kg/cm2
Heat Expansion Coefficient: 0.0050 mm/m°C
Water Imbibition Coefficient: 0.003200
Impact Strength: 86 cm
Frictional Wear: mm
Mass By Unit Of Volume: 2661 kg/m3
Hardness (Moh's Scale):
Note: These figures and details are given for guidance purposes only, no reliance should be taken as to their accuracy.