After a large block of granite intended for use as a countertop or other building project is cut from a quarry, it's sliced into thin sheets called slabs. The slabs are polished and bundled into groups of 8 to 10 slabs from the same block so that the slabs can be kept together as they're shipped from the quarry to a building supplier. Because the color and patterning of the stone can vary considerably from block to block, and even within a single block, tracking of the slabs is crucial in ensuring that the appearance of the stone is consistent in jobs that require multiple slabs.
Granite slabs are typically between 9 and 10 feet long and between 5 and 6 feet wide, although the exact dimensions of individual slabs vary. The typical surface area of a slab is about 45 square feet, but because there will be some waste during the process of cutting the slab into a counter top, the usable yield of a slab will be much less than that. Consequently, large kitchen counter projects will often require more than one slab.
Slab Thicknesses and Weight
Granite slabs are typically either 3/4 inch or 1 1/4 inches thick. The thicker slabs usually weigh approximately 19 pounds per square foot, while the thinner slabs weigh less than 13 pounds per square foot. Both thicknesses may be used for counter tops, but 3/4-inch granite is usually laminated into a double-thickness slab, so the finished counter top is 1 1/2 inches thick.
Some suppliers offer granite slab remnants in non-standard sizes. These remnants are either pieces left over from standard slabs that have been cut down for other projects or slabs that have been cut from unusually small blocks so that the slabs are not big enough for typical counter tops. Remnants are usually less expensive than standard slabs and may be suitable for smaller projects such as kitchen islands, back splashes, table tops or bathroom vanities.