Marble Vs. Cultured Marble
- Marble is a metamorphic rock, formed from limestone by heat and/or pressure within the Earth, which cause recrystalization. Marble is found in many places in the world, including Europe, Great Britain, India and the U.S. Impurities in the original limestone affect the resulting marble's color and type. Pure marble is white, but the stone can be reddish, yellow or green, depending on the impurities present.
It is difficult for quarry miners to split marble into uniformly sized slabs; they must carefully cut it. They cannot mine it with explosives because it will shatter. Marble blocks must be mined with machines that make grooves in the rock. Geologists classify marble by its composition and its ability to be polished. - Marble Works of San Diego, a manufacturer of cultured marble, produces cultured marble from calcium carbonate, or limestone, granules. Limestone is the same mineral from which natural marble forms. Marble Works custom-makes its molds, as do many other manufacturers, and coats the inside of them with wax and a clear gelcoat of polyester resin. After the gelcoat hardens, a mix is poured in that will cure to be the cultured marble. The mix consists of polyester resin, limestone, aggregate fillers, pigments for color and hardeners. Once the mix cures to hardness, the molds are removed and the cultured marble is trimmed and polished, ready for shipping and installation. This process is typical of the manufacture of cultured marble.
- Natural marble is very heavy and is fairly brittle because of the veins running through it. These qualities complicate cutting to the size desired. Cultured marble weighs much less than natural marble, and manufacturers design cultured marble molds in advance, thus achieving a perfect fit. However, cultured marble is not suitable for the carving of sculptures since it has a hard outer coating.
Natural marble is very porous. It must be waxed and sealed regularly to prevent airborne or water-borne contaminants from staining it. It is very difficult to remove a stain from natural marble. Cultured marble, by contrast, has a hard, impermeable surface created by the gelcoat that lines the molds within which the stone cures. It is much easier to clean because of its low porosity. - Neither natural marble nor cultured marble is easily repaired if a break or crack occurs. A few more methods of repair are available for cultured marble than for natural, but they often fail to provide very satisfactory results.
- Natural marble is far more expensive than cultured marble, not only because it is a non-renewable resource, but also because it must be shipped from wherever it is quarried. Cultured marble can be made relatively close to the location in which it will be installed. Fewer work hours are required to produce cultured marble.