Natural stone is formed by nature and quarried, not manufactured. No two quarries, blocks, lots or pieces are identical: color, veining, pores, fissures, density, absorption, iron content and finish can all vary, and samples, photos and displays may not match the material you receive. Variation is part of the beauty of natural stone and is not a defect in itself.
OC Stone Guide is an independent publication that curates and links to recognized authorities, including the Natural Stone Institute (NSI), ASTM International’s dimension-stone standards (such as ASTM C503, C568, C615, C616, C629 and C1527), ANSI A326.3 for dynamic coefficient of friction, the California Contractors State License Board, and your city or county building department. We are not the authority on any of these subjects. We don’t sell, manufacture, install, test or warrant any stone, product or installation, and nothing on this site or in our guide is a warranty, guarantee, specification, or engineering, legal or code advice.
How a stone looks and performs over time depends on the specific material, how it is selected, installed and maintained, the site and climate, and how it is used. Heat underfoot, slip resistance, staining, wear and color change cannot be guaranteed. Ask your supplier for test data on the exact stone and finish, follow the manufacturer’s instructions for sealers and cleaners, and rely on licensed professionals and your building department for design, structural, drainage, code and permit decisions. Any warranty comes only from the seller, manufacturer or contractor, in writing.
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