Granite worktops - how are they made?
Wednesday, 31st July 2013, Paul Dore
It's one of the most coveted features of any kitchen design: a granite worktop. Consistently popular, this hard-wearing, highly-polished and extremely desirable material turns any bland room into one you'll want to entertain in, spend much more time in and one where you won't need to worry about stains, marks and cuts on the work surfaces. When they coined the phrase 'rock hard', it must have been about granite.
From mining to installation, the manufacture of granite worktops is a fascinating process. Here's how they are made:
What IS granite and where does it come from?
Granite is crystalline igneous rock, that comprises mostly quartz. It is the quartz that gives granite its signature hardness and beautiful look. It is formed at huge depths and under extreme pressures from cooled magma, occurring in different colours dependent on its mineral composition. It is found all over the world, from Cornwall to Rajasthan via Vermont and beyond. In fact, many regions are appropriately self-styled as 'the granite capital' or 'on the granite belt' as evidence.
Mining and cutting
The rock is drilled and blasted out of the mine, then cut using special machines into blocks of about three metres in length and one and a half metres wide. These slabs are further chopped into smaller 'scants' which have a depth of 20 or 30mm and are polished on one side. Once this has taken place, the granite is shipped to its next destination, ready to be fabricated.
Templating and fabrication
Although the 'main' cutting will be done at the mine, much will need to be done by the vendor's experts as per the customer's bespoke design wishes. For example, the client may want rounded edges, splash-backs or perhaps a breakfast bar.
In order to work out where the joints and cut-outs (spaces for the sink, taps, hob and possibly drainer grooves) might go, also to configure whether a large slab of granite can physically fit into a kitchen, a real-size template will be created by a professional 'templater'. This measures the surface to be covered with granite and ensures that cupboards or units are sufficiently weight-bearing. The finished, signed-off template represents the proposed design and from this, the granite can be fabricated accordingly, using state-of-the-art machinery.
Granite kitchen worktops can be fabricated in a variety of finishes, each of which is achieved using different-textured diamond pads. The most common finish is a high shine, for which the finest pads will be used. That said, many people like a 'honed' finish, one which is matte and smooth, while others might opt for something a little more unusual, such as sand-blasting, for a 'raw' look.
After this, the granite will receive its first coat of sealant, which increases its resistance to liquids, acids, heat and other marks.
Fitting, surprisingly, does not take that long - usually no more than four hours. The granite is effectively put into place using its own weight, levelled with silicone beads, then chemically set in place. A second coat of dry sealant will then be applied, for additional protection.
The difficult part will be trying not to use the work surfaces for the requisite couple of days after installation!
There's little maintenance required with granite worktops, other than the usual cleaning, though guidance will usually be left with the customer. That means, therefore, that the client is simply left with a beautiful granite worktop; a feature that they will invariably want to show off to their nearest and dearest, deriving years of pleasure and adding untold value to their home into the bargain.