With natural and manmade stone worktops dominating the top trends list, we set off to discover where they originate from, and the journey they take, before reaching your home.

It’s important to know where things come from. Be that the food on your plate or the clothes on your back. And here at KBB, we feel the same about kitchens, and everything that goes into them. Which is why when I was offered to visit Neolith’s headquarters in Spain, to be shown how sintered stone (a synthetic material formed by heated minerals) is made, I jumped at the chance.

Scorching heat and slightly uncomfortable factory shoes aside, I was fascinated by its production process. This got me thinking about other stone worktops – both natural and manmade – and the journey they take from rock or powder to full-blown countertops. So, I set out to learn all I could, to help you make more informed decisions about the places you pick your worktop from, and the materials that suit you.

Where do natural stone worktops come from?

Let’s start with the real deal – created from pure rocks made by Mother Nature herself, natural stone worktops, including marble and granite, follow a seemingly simple manufacturing process: the stone is extracted from a quarry, shipped to a block yard or cutting factory, cut into slabs, then shipped to a wholesaler or fabricator before being cut into the finished surface. Is the process that simple, though?

The manufacturing process

Michael Cohen, owner of marble and natural stone wholesaler Imperial Stone Group, will tell you otherwise. Michael travels around the world to source the most immaculate, unprocessed blocks of stone (think quartzites, onyx and travertine) from quarries in countries such as Italy, Portugal, Brazil and Greece.

Once he finds the ‘perfect block’, this is compressed, in a process known as vacuum resin – where the entire block is covered with a plastic film and resin, then squashed and shaped as a square.

This is then transported to a gang saw and cut into two or three centimetre-thin slabs, “just like cutting a slice of bread,” explains Michael. “The slabs then go through quality control to ensure there are no cracks, then resin is applied on the back of the slabs with a mesh, and on the front, and then they’re ready to be polished.”

Stone yards

One final inspection is carried out before these are shipped to stone yards in the UK. This is where homeowners, designers or architects can walk through rows and rows of slabs and decide what they want for their kitchen. From there, the slab is sent to the customer’s preferred fabricator who will start working on it as per their requests – thinking about elements such as the final finish and the design of the vein.

“Cutting extremely hard materials like the Taj Mahal quartzite, or the soft and delicate marble, is challenging; they need to be handled with care, by fabricators who know how to do it,” continues Michael.

Producer of natural stone Lundhs follows a similar production process, extracting raw blocks of stones such as Larvikite and Anorthosite from their own quarries in Norway, exporting them to factories in Italy where the slabs are created, and then to UK distributors and fabricators.

“The quarrying process is often the same, but the traceability of colours and qualities throughout the value chain is unique to us,” says marketing and business director Hege Lundh. “Each block we extract is given a unique block number, making our stones traceable from quarry to installation.”

It’s worth noting that European quarries have rules in place by the European Union, which can allow for better reassurance that they are well-run.

How is manmade stone produced?

When it comes to the non-porous sintered stone, its production “involves subjecting a mix of raw materials to extreme pressure and high temperatures, mimicking the natural process of stone formation but in a much shorter timeframe,” explains Ross Stewart, Neolith’s UK senior sales manager.

Picture materials such as stone dust, chalk, recycled glass and porcelain, and minerals including quartz and clay, being placed into a mill where they’re mixed with water and crushed to a fine powder, before being filtered out for impurities.

This powder is then spread on the production line, where it’s pressed and turned into rectangles. These are dried out to remove all humidity, and then digitally decorated with intricate designs and patterns.

The slabs are then heated in special kilns, in a temperature of up to 1200°C – this step is called sintering and it’s the most challenging part of the process, says Ross. “You need the perfect curve of temperatures, to ensure the slab can be cut and installed perfectly.” Quality control follows and, soon enough, the slabs are ready for the kitchen.

Engineered surfaces

Meanwhile, engineered stone surfaces, also manmade, are slightly different in composition. Engineered quartz, for instance, is made from natural quartz crystals bound together with resin and pigments. Cosentino’s Dekton surface also includes natural quartz, but in a lower percentage, mixed with glass and porcelain.

“It’s manufactured using ‘sinterized particle technology’ (SPT), a process that perfects in a few hours what nature creates in thousands of years,” says Katie Parry-Stone, retail expert at Cosentino UK. She goes on to explain that Dekton’s press generates a whopping 25,000 tons of uniform pressure, which eliminates pores and micro-defects.

Either manmade or natural, that pretty slab, with elements potentially thousands of years in the making, will have been on an incredible journey of self-transformation, fuelled by creativity, expertise, and often unbelievably high temperatures. Something to think about, the next time you pop down that cup of tea on your own stone worktop.

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