This guide will explain what types of stone are available through Stoneworks, and will take you through the properties of each stone along with its advantages and disadvantages. This should help you to make a more informed decision about which stone is best suited to your project in terms of matching your design ideas and choosing a stone which is suitable for the intended use.

Granite

The word granite comes from the Latin word granum, meaning "grain", and it is so named because the stone is essentally contstructed of billions of minute crystals. The granite group is one of the most versatile stone types available as it is capable of taking a wide variety of finishes which allow the designer to custom-tailor the stone in a myriad of ways.

Resistance to scratching and durability in foot traffic areas are largely dependent upon the hardness of the minerals that make up the stone. The relative hardness of a stone can be measured on Moh's Scale, which ranges from 1 (Talc) to 10 (Diamond). On this scale, your fingernail would measure 2.5, a copper coin would be around 3.5, and a steel knife would measure about 5.5. In most granites, the primary minerals are quartz and feldspars, accounting for approximately 90% of the stone, and mean that granite measures around 6.5 on the Moh Scale, making it a very hard substance and so ideal for areas of heavy foot traffic.

Granite is also ideal for kitchen worktops; not only is it extremely hard and durable, but it is also resistant to changes in temperature. If you heated an entire 1.5 metre granite worktop to the temperature of a cup of tea - which would be no mean feat - it would expand by less than 1mm. A granite worktop is also very strong, capable of withstanding 1000 lbs/square inch.

The main disadvantage of granite is its cost compared to laminated worktops, but when the advantages of durability, temperature resistance, strength and sheer beauty are considered, it is definately a worthy investment.

Marble

Marble is a metamorphic rock, meaning it has been created as minerals (mainly calcite and dolomite) have been heated and then changed form as the rock has cooled. Marble is very popular as it can be highly polished to give an excellent glossy finish.

A marble of pure calcite or dolomite would be white. Marbles are available in a vast array of colours, and the variety of colours is the result of impurities found in the marbles. Less pure marbles are actually weaker, making them less suitable for areas of high foot traffic or kitchen worktops.

Like granite, the main disadvantage of marble is its cost, but the sheer majesty of a bath, sink, vanity unit, fireplace or tiled area in marble cannot be matched.

Travertine

Travertine is often counted as a marble in commercial circles, but at Stoneworks we separate it as a different category as it is not, geologically, a true marble; it has some characteristics of limestone as well.

Travertine is formed through deposition; this means that is builds up slowly as mineral deposits are left by running water, and is mostly found in the hot springs of Turkey (try searching for photographs of Pammukale, Turkey, to see travertine in its natural environment). Travertine is more similar in appearance to limestone, having more uniform colouring, but it boasts the hardness of marble and can be polished to a close standard.

Travertine often has naturally formed pocks and holes, and we offer tiling with these holes left for a more traditional feel, or filled in with a hard-wearing compound to give a smooth finish.

Limestone

With a hardness of around 3.5 on Moh's Scale of Relative Mineral Hardness, limestone is not suitable for use as kitchen worktops, and Stoneworks do not recommend that it is used in areas of dense foot traffic. It is, however, suitable for tiling areas of low foot traffic, wall tiles, sinks, vanity units, baths or fireplaces.

Like marble, the colour in limestone is altered by the presence of impurities but, unlike marble, limestone is a sedimentary rock, meaning it is made of layers of silt and organic material which has settled and compacted under its own weight at the bottom of rivers, lakes or sea beds. 

Due to high absorption and susceptibility to staining, limestone is not generally used is applications where it comes into contact with soil, and proper care should be taken to treat limestone with purpose-made products when used indoors. This is easily affordable, though, as limestone is a more economical option than marble.

Slate

Slate is a dense and fine grained rock, but it is still relatively soft (around 3 on Moh's Scale). It is a metamorphic rock which is created through compacted sedimentary stone such as shale. Despite being fairly soft compared with granite or marble, slate is very strong even in thin sheets due to the layered way in which it forms.

Outdoors, some slates can fade, but for interior use they will not usually fade in this way. Slate is dark in colour, being predominantly black or grey, and so provides a cheaper contemporary tiling option than granites.