The words ‘natural’ and ‘stone’ are more blatantly abused by the makers of man-made products all the time. They even sometimes denigrate natural stone as a ‘quarried product’. NSS columnists Alan Gayle and Barry Hunt argue that the words should be reclaimed by the stone industry.

Alan Gayle
I got a new smart phone last year and, being a bit on the clumsy side, I was soon scouring Google for a protective case. I ordered a leather case for the princely sum of £3.95. Including delivery! Excellent bargain.
Or so I thought.
When the case arrived I realised it wasn’t leather at all. When I checked the small print it said ‘PU leather’, which, of course, means it is a man-made product.
The leather and stone industries share the same problem: imitators confusing customers with misleading definitions, euphemistic names and deliberately confusing language.
Cast stone, reconstructed stone, reconstituted, engineered. Call it what you will, it’s all man-made material masquerading as the genuine article.
Cast stone / reconstructed stone / reconstituted stone /engineered stone (delete as appropriate) is to stone what PU leather is to leather.
The wood industry doesn’t allow chipboard or MDF manufacturers to confuse consumers by using the word ‘wood’, but the stone industry has allowed the word ‘stone’, even used in conjunction with the word ‘natural’, to be used for a wide variety of man-made products almost without challenge.
And the longer those who aren’t selling stone get away with it, the bolder they get and the worse the problem becomes.
When I worked for Forticrete about 15 years ago, it produced a polished concrete block called Medici. Now that same concrete block (or one very similar) is marketed under the banner of ‘polished marble’. And guess what they call the white block in their ‘polished marble’ range? Carrara. Why call it anything else when you know nobody will complain or challenge you? Carrara Polished Marble from the Medici range. It sounds so authentic – no wonder consumers don’t know the difference between concrete and stone.
So why do the concrete product manufacturers do it? And why do we in the stone industry let them get away with it? I have no answer for the second question but I can certainly answer the first. In his recent article ‘Naming: The Most Important Marketing Decision’, Neil M Brown, Chairman of the US-based Construction Marketing Association, says: “First, there is great power behind successful company or product naming. While not even the best name can save a bad product or idea, the ideal name can have tremendous impact on its success.”
According to the UK Cast Stone Association (UKCSA) the definition of ‘cast stone’ is “any material made with natural aggregates and cementitious binder that is intended to resemble and be used in a similar way to natural stone.”
Note the use of the words ‘natural aggregate’. Could it possibly be they just want to legitimise their product and confuse the public by using the word ‘natural’ whenever they can? And why do they say ‘cementitious binder’ instead of cement? Could it be because everyone knows cement is used in concrete and they want to distance themselves from it?
These definitions confuse the public even further when you see that Haddonstone (and others) describe natural stone as ‘quarried stone’.
Do you see what they’re up to? Use the word ‘natural’ in the description of their own product then omit its use from what really are natural products and use instead a word, ‘quarried’, that has negative connotations in most people’s minds – largely because most people associate it with the huge operations of cement and aggregate production, not the almost cottage industry of natural stone.
If you think this is innocuous and I’m over reacting, think again. The word ‘natural’ or ‘naturally’, along with words such as ‘sustainable’, ‘low-energy’, ‘proven’, ‘guaranteed’ and a few others, are ‘words that sell’ (apologies for the marketing jargon) in today’s ecoconscious building industry.
The Brick Development Association (BDA) knows the value of it. It has created an entire advertising campaign around the word ‘naturally’. Make no mistake, the BDA knows exactly what it’s doing when it describes natural stone as ‘quarried stone’ and bricks as being made from ‘naturally occurring aggregates’.
I have no problem with coloured concrete being used as imitation stone. There is certainly a market for imitation stone and there might even be some good products. It is entirely understandable they want to use the kudos associated with natural stone to market those products. What is less understandable is that they get away with it because in doing so they devalue products that really are made of natural stone and nothing else.
To be fair, Haddonstone make a decent product and although the terminology is clearly intended to disassociate it from the concrete that it is, the company is by no means the worst offender and at least it does describe its products as ‘cast’ stone.
Not everyone is even that transparent. One website I have come across, Fernhill Stone’s, uses a term I hadn’t come across before: ‘cultured stone’.
In the FAQs on its website the company includes the question: ‘Is it natural stone?’ The answer is: “The products are cast in moulds using a technique process [sic] that replicates existing colours and textures with meticulous detail. Each colour and texture has its own blend of ingredients producing the look and feel of natural Stone.” Note the word ‘no’ does not appear.
You can view the website for yourself at www.stonecladding.co.uk.
According to UKCSA, “independent [sic] research has shown that cast stone can weather like natural stone and looks much the same”.
What the report actually says is: “Weathering” [limited to efflorescence and particle retention in these tests] “was similar in cast stone to that in control natural stone.”
What was the control natural stone? Concrete products from seven different companies were tested. How many natural stone samples were used? Who decided that the ‘control natural stone’ was sufficiently representative of the whole stone industry? And who decided weathering was a question only of efflorescence and particle retention?
Then the research is used by companies such as Proctor from Leeds, which cites it in its assertion that: “After installation, cast stone weathers in the same way as natural stone.” (More about this in the article below by Barry Hunt.)
Europe has protected the geographical status of Champagne, Gorgonzola cheese, Cornish pasties and Melton Mowbray Pork pies, why not Portland, Bath and York stone? Why not Carrara marble?
Industries as diverse as wood and wool have managed to protect the words that describe their raw material. It is time the stone industry did the same.

Barry Hunt
Give a piece of stone to 10 geologists and they might come up with 10 different names for it, depending on whose classification systems they use. And all of them might be technically correct with their choice. So if the scientists are confused, what hope is there for anyone else?
Understandably, the stone industry developed a greatly simplified approach to stone classification, which created a number of issues leaving the door wide open to abuse.
European Standards dealing with stone description and classification have tried to address the confusion by providing a clear set of rules for all to follow, although the stone industry has not woken up to this and the potential benefits it offers yet.
If we all named our stones correctly, it might be easier to take issue with those man-made materials that include a reference to a type of stone or mineral, have a scientific sounding name, or use misleading adjectives to suggest a wholly natural origin.
We might also be able to take greater issue with the properties of these materials and the range of claims made for them, many of which appear to be either irrelevant or unsubstantiated but add gravitas to mislead the typically uninformed end-user.
Let us look at some of these artificial materials. I have investigated many of them during various construction failures.
Giving artificial materials misleading names started as early as 1722, when Richard Holt took out a patent for making artificial ‘stone’, which appears to have been a type of ceramic. The first artificial ‘stone’ produced on a factory scale was Coade Stone, which first appeared in 1769. It was sometimes marketed as ‘Lithodipyra’, which is a fancy way of explaining the double firing process involved. The ‘Litho’ part clearly suggests stone, so maybe this is an early instance of a deliberately misleading description. This aside, Coade Stone has proven to be an exceptionally robust material.
At the Great Exhibition of 1851 a block of a new type of cast cement-bound material was shown. Someone remarked that it looked like Portland stone, so the name of the cementing agent was born: Ordinary Portland. This might be apocryphal but it demonstrates how names associated with natural stone have always been attractive to the makers of artificial imitations.
One of the most commonly used terms for such concrete products is ‘cast stone’, which even has British Standards and a UK association representing the industry that makes it. How has this arisen? All these materials are is concrete blocks with the same properties as most concrete blocks – low tensile strength, propensity to shrink (with associated cracking), a potential for reaction, a potential to suffer reinforcement corrosion where reinforcement is used, and susceptibility to leaching issues.
The finish of most cement-bound materials is typically light cream to buff, providing a very general mimicking of many Jurassic Period limestones, including such well known stones as Portland and Bath. However, the concrete products struggle to replicate the subtle colour variations of natural stone and don’t have the fossils, laminations and other natural structures that provide the true aesthetic of actual naturally occuring stone.
In a relatively short period, the granular porous structure of cement-bound materials can attract and trap dirt and promote moisture flow leading to quite extensive deposition of carbonate surface deposits that result in often dramatic colour changes.
Where shrinkage cracking is present, this can become highlighted by dirt. Cement-bound units also have some limits on size, resulting in features such as cornices suffering from excessive jointing.
Being cast, installation is typically carried out by people who lack the rigorous training of a stonemason, so lipping, recessed jointing, mortar smearing and other issues are not uncommon.
From a mechanical point of view, most cement-bound materials can only really claim to exhibit strengths that match the weaker stones used for block masonry.
They certainly do not match harder and denser stones. Even when they are carefully engineered they can still be a fraction of the strength of granite and marble.
Some cast materials have also performed disastrously when subjected to frost, and the presence of reinforcement can lead to considerable spalling, something I recently encountered at a major institution with thousands of pedestrians passing underneath failing façade features every day.
Natural stone is widely used for decorative finishes. It is the crystalline nature of many natural stones that allows incident light to be reflected from deep within to add depth to the changing appearance. In contrast, many cast materials, whether cement or resin bound, appear flat and without lustre because the cementing agents are typically opaque and reflect light from the surface rather than from within.
High value artificial products such as kitchen worktops may appear dull by comparison with their natural counterparts. The organic base of resin products typically will be less resistant to scratching than the siliceous minerals that are commonly present within most granites and other igneous rock types.
How well an artificial worktop performs may be down to the size and grading of the aggregate particles and whether these are glassy or macro-crystalline, so that there is some degree of light play.
Some resin-based worktops suffer slow warping, leading to cracking, which tends to manifest itself particularly rapidly if sharp-edged cut-outs are performed.
Quartz ‘stone’ is a recent addition to the pantechnicon of names being applied to artificial products seemingly trying to masquerade as natural stone.
They are often described as ‘engineered stone’, which is hokum and so much in the style of estate agent speak. Quartz is a ubiquitous mineral, usually comprising the majority of the sand grains on a beach or in a river, so calling something engineered stone is just another way of describing an aggregate within a binding agent. In some instances there is even very little quartz, with glass fragments and other recycled materials being used instead.
Sadly, the situation will probably continue unabated and can therefore only get worse. It is hard to envisage the stone industry fighting its corner, especially when this has been going on for around 300 years. Educating the customer seems the most obvious answer, but that is easier said than done.