Natural Stone is not manufactured; it is a product of nature. Blocks are removed from the quarry, slabs are cut from these blocks, and the slabs are further fabricated into the final stone to be installed. Each block is different; each slab is different. Skillful blending or matching of the dimension stone blocks, veneer panels, tops, etc., results in a beautiful blending of nature variety and design.
In contrast to the uniformity of materials produced by machine or assembly line, stone naturally varied appearance has wonderful character. Uniformity of material, when applied to natural stone, is a term of relative value that needs to be understood when making a selection.
An excellent choice for kitchen countertops, floors, and other heavily used surfaces. Statistics from various sources indicate that the granite quarried in the countries of China, India, and Brazil comprises approximately 2/3 of the granite used worldwide. There are granite quarries in operation in dozens of countries and it is one of the most popular natural stones on the market. New granite resources are continually being located and developed throughout the world. Granite has long enjoyed use as an exterior cladding and pavement material.
Its inherent strength, abrasion resistance and superior weathering durability are likely to keep it one of the preeminent material selections available to today's architects. Granite has also been employed as the traditional material for municipal curbs, where its strength and durability have been documented with decades of vehicular abuse. In the northern climates where snow melting chemicals are used heavily, granite has resisted the attack of these caustic agents. Being one of the hardest of the dimension stone types, granite was historically avoided by the smaller, local stone fabricating shops, who favored marbles and limestones due to their easier working properties.
A recent boom in the supply of affordable machinery and abrasives technologies eliminated these previous difficulties in fabrication. As a result, the use of granite has skyrocketed in residential interior applications. Available in a striking array of colors, granite's durability, longevity, and economy make it ideal for kitchen countertops and other heavily used surfaces, including table tops and floors. Some synthetic surfaces scratch easily, while the hardness of the minerals comprising most granites surpasses that of the utensils that are used on them, resulting in excellent scratch resistance. Granite is typically heat resistant up to temperatures of ±250°C (±480°F) Direct application of localized heat sources is discouraged since strong thermal gradients within the stone can initiate cracking.
According to the Marble Institute of America Technical Bulletins studies of bacteria retention on common countertop surfaces have proven granite to be superior to the majority of surfaces employed for that purposes. Absorption rates (% water, by weight) of stones in this group range from 0.05% to 0.40%, indicating that the available pore volume capable of harboring a staining agent is very slight. Impregnating repellents are sometimes used to further reduce the stain resistance of these materials.
Limestone is a sedimentary stone with at least 50% calcite or calcium carbonate content. Almost all limestone is composed of grains or fragments of biologic origin, ranging from fossils to dinosaur bones. Most limestone is marine in origin, composed of micro-sized fossils of marine organisms like the shells found on most beaches. It is very common to find pieces of shells in limestone tiles.
Marble is a metamorphic rock found in the mountainous regions of most countries of the world. Marble quarried in India, China, Italy, and Spain represents the majority of marble, in terms of volume, that is utilized worldwide. Because of its beauty and elegance, marble is a popular choice for countertops, floors, foyers, fireplace facings and hearths, walls, and windowsills. With its inherent warmth, marble adds a sophisticated element to the area in which it is installed. Its naturally random appearance, engineering characteristics, and ease of maintenance makes it a premium choice for floors, wall claddings, table tops, wainscot, floors, and vanity tops.
Many marbles are well suited for wet area application, which extends the versatility of this material to include tub decks and showers. The calcite crystal is the basic building block of true marbles. The calcite crystal is vulnerable to attack by mild acids, including those commonly found in kitchen and bar settings. The user selecting marble for these applications should be aware of, and accepting of the maintenance and patina that is to be anticipated with this combination. Acid rain and other weathering elements can also affect exterior marble installations, and are generally limited to white marbles, with some exceptions.
Often mistaken for marble is serpentine, which is actually magnesium-silicate based as opposed to calcite based. As a result of the different mineralogy and whole rock chemistry of serpentine, it exhibits greater acid resistance and abrasion resistance than true marble does. These properties make serpentine a common choice for both kitchen counters and exterior applications. Onyx is often confused with marbles, yet it is a significantly different rock type.
Onyx is a sedimentary rock, formed as stalactites and stalagmites in cave interiors. This formation method results in the cryptocrystalline construction of the rock fabric, and it is the size and uniformity of these crystals that contribute to the classic translucent property of most onyx varieties. While vulnerable to chemical and abrasive attack, the decorative appeal of onyx is perhaps unsurpassed by any other material.
Versatile, Chemically Resistant Materials A traditional use of both these materials was the laboratory table top in chemistry labs. That application alone should serve as a great testimonial to the chemical resistance of the materials. Being of the softer varieties of dimension stone types, neither of these materials is known for particularly high abrasion or scratch resistance, yet they are both used a flooring and countertop products.
Soapstone is highly heat resistant, and has been used in fireplace surrounds frequently to take advantage of this property. Slate, being of laminar construction, has the ability to be processed into thin sheets and still maintain serviceable strength and rigidity. This property makes slate the only dimension stone having been used for blackboards and roofing shingles. It was also traditionally used as the cloth-covered playing surface of billiards tables.
Travertine is a calcium-based stone. Travertine is generated by the deposit of calcium carbonate resulting from water springs and streams running through the stone. Every time a drop in pressure or change of temperature occurs, the water releases carbon dioxide as gas, much like carbonated beverages. This gas causes holes to form in the travertine. These natural pores are still going to be present once the blocks are cut into tiles.
The amount of holes depends by how compact each travertine type is and it varies greatly by the type of travertine. The pores present in the tiles can be filled with a paste made of cement and pigments. However, it is important to note that these void spaces are a distinctive character of travertine tiles and they are always going to be present to a certain extent.
A mirror-like, glossy surface that brings out the color and character of the stone to its fullest, because it optimally reflects the light.
A velvety smooth surface with little or no gloss. The degree of honing depends on the stone, but may vary from light to heavy.