Granite – applications and appearance
The term granite has been applied to almost any igneous stone that can retain a polish. True Granites provide many of these stones but other types of igneous stone that may fall into this classification include syenites, gabbros, dolerites, and diorites. The metamorphic stones gneiss, schist and granulite are frequently also included in this ‘Granite’ classification. The formation of these igneous rocks by the slow cooling of molten minerals such as quartz, feldspar and hornblende has resulted in a wide variety of colours and grain patterns. In the United Kingdom the quarrying of Granite is concentrated in a small number of locations. Those of particular importance may be found in Cornwall and Devon, Cumbria, at Peterhead and Aberdeen and on the east coast of Scotland. The main sources for imported granite are Scandinavia, South Africa, Sardinia, Spain, India, North America, China, Portugal and Brazil.
The interlocking crystal structure imparts both the high strength and low porosity necessary for a wide range of applications other than just flooring; these characteristics are also important in allowing successful use of slabs that are thinner than other types of stone. It is extremely hard and heat resistant, and is therefore completely suited to worktops. You can cut food items directly on the worktop surface as it almost impossible to cut or damage with a conventional kitchen knife. You can also take dishes directly out of the oven and set them on a Granite worktop, as it is not susceptible to cooking heat.
The amazing colour choice includes fine and medium grained silver grey from Devon and Cornwall and fine grained pink from Scotland, whilst other countries provide dense, very fine grained materials with reflective crystals such as larvikite (e.g. blue and emerald pearl) from Norway; reds from Scandinavia and India; large grained brown from Finland; yellows from Brazil; and the delicately mottled greys, fawns and pinks from Sardinia.
The surface finish affects the appearances of Granite and those available include sawn, flame textured, dolly pointed, fine axed, rough punched, honed, bush hammered and water jet. It is in the gloss polished form, however, that these granites reveal fully their colours and grain patterns.
Very hardwearing and physically strong, granite is largely unaffected by erosion, pollution or atmospheric attack. Facades are generally self cleaning, although eye level areas benefit from occasional cleaning as for glazing. A polished finish is almost indestructible.
Caring for Granite
Granite is extremely durable, but it can be necessary to maintain the surface periodically through simple cleaning and polishing. This will usually restore the granite to its original state.
- Clean surfaces with a few drops of neutral cleaner or a mild liquid dishwashing detergent and warm water.
- Use a clean rag for best results.
- Too much cleaner or soap may leave a film and cause streaks.
- Do not use products that contain lemon, vinegar or other acids on the granite as the high acid content may etch the surface.
- Rinse the surface thoroughly after washing with the soap solution and dry with a soft cloth.
- Change the rinse water frequently.
- Do not use scouring powders or creams; these products contain abrasives that may scratch the surface.