What Every Stone Owner Should know .02

WARPING OF GREEN MARBLE
Several types of thin stone tiles are very susceptible to warping. Many of the green marbles and a few agglomerate marbles are notorious for this warping condition. Many of an installer has had the surprise to find that their tile installation has become warped overnight. Why does this a happen and can it be prevented. Warping is caused by water. Green marble set with any water-based material will have a tendency to warp. The mechanism of why the tile warps is somewhat a mystery. Some believe that the water fills the pores of the stone and when the water evaporates the orientation of the stones crystal change and cause it to warp. Whatever the reason, one thing is for sure; green marble can warp when set with water based materials.

Cure: Once a green marble tile warps it is difficult to repair. Attempts have been made to grind the tile flat, but this usually fails since additional water is introduced during the grinding process. The green simply warps again.

Prevention:
The only way to prevent warping is to install it properly with non-water based material such as epoxy. Some installers have also been successful in sealing the back of the tile with epoxy and installing it in water based system. Do not attempt to seal the back of the tile with a silicone sealer. The silicone acts as water repellant and will cause the setting material to fail resulting in a bond loss.

	grinding This is the second stage in securing a flawless surface. This stage will remove all scratches from any de-lipped surface.

	sealer Impregnation: This is commonly known as sealers. This is the first stage in preserving and maintaining your investment. This stage should occur ever six to eight months. There are three types of impregnation (solvent, water, silicone based), regardless to brand. This will stop most water base stains from occurring. It also will stop the stone from been damage beyond repair.

	AGGLOMERATE A stone type composed of many pieces of stone held together with polyester or similar resins.

	epoxy EPOXY A two part resin with superior adhesion properties used for joining and filling stone. Also used for grouting stone and tile.

	Marble MARBLE: CHARACTERISTICS This standard includes general information on the characteristics and common uses of marble and identifies typical problems associated with the material. INTRODUCTION Marble is an extremely hard, metamorphic stone composed of calcite (CaCO3). It is formed as a result of the recrystallization of limestone under the intense pressure and heat of geologic processes. The effect of this process is the creation of a stone with a very tight crystalline structure and small but definite porosity. Because of its structure, marble can take a very high polish and is a very popular decorative stone for architectural and sculptural uses. The limited porosity of marble, especially polished marble, makes it less vulnerable to the leaching effects of water. Calcium carbonate, however, of which marble is composed, is highly susceptible to attack by acidic agents. Marble is readily dissolved by acids, even very dilute acids, however the actual results of acidic exposure will vary with the nature of the acid. Chlorides, nitrates, sulfates and other chemical compounds react differently with marble and produce various by-products, which have a wide range of solubility and impact on the durability of marble. For this reason, it is always important to determine the exact type of pollutants causing marble deterioration. Marble itself can be of two types, one composed of calcite and the other of dolomite. Dolomitic marble is much more resistant to acid attack than calcite marble. The color of marble ranges from the brilliant white of calcite to black, including blue-gray, red, yellow and green, depending upon the mineral composition. TYPICAL USES Marble has many decorative and structural uses. It is used for outdoor sculpture as well as for sculpture bases; in architecture it is used in exterior walls and veneers, flooring, decorative features, stairways and walkways. The way in which the stone is used may be a factor in limiting or controlling the severity of exposure. The use or function of the marble may also affect the feasibility of applying certain treatments, but type of use is not the primary factor in the major types of deterioration and damage to which marble is susceptible.