Sourcebook of Decorative Stone An Illustrated Identification Guide

IntroductionThere are thousands of different decorative stones, and they are used in every country of the world. Look around and you'll see them adding color to the fronts of stores. They form the practical, hardwearing cladding to many architectural interiors and exteriors of company offices and public buildings. Enter a church, synagogue or mosque and you will see them, often in beautiful patterns, cladding walls and floors, lecterns and altars. Memorials are carved into them, graves are marked with them, and they make superb raw material for sculptors to carve. Beautiful, natural rocks have a functional place inside our homes too, forming practical surfaces for kitchens and bathrooms, or made into the vases, tealight holders and other ornaments so popular with contemporary interior designers. Of course decorative minerals are widely used in jewelry too. Stone has a timeless quality, and some of the most exquisite ornamental stones are found in the decoration of precious antique furniture. The tradition of using polished stone for decoration is shared among civilizations all over the world, going well back into antiquity. Turning Rock into a Thing of BeautyIt has to be admitted that most natural rocks are not particularly attractive to look at. Even the stones in this book, when roughly hewn from the ground, are generally rather dull. It is when they are polished, buffed to a bright reflective luster, that colors are enriched and patterns and structures sharpened, and their inherent natural beauty s revealed. Not all rocks have decorative value. They must have a compact and cohesive structure that enables them to be sawn or shaped without splitting or breaking up, and they must have an attractive appearance. They also need to occur in nature in sufficient quantities. Some semiprecious minerals are so valuable that quite small deposits are commercially viable. For "dimension stone"-- that is slabbed and polished for architectural use -- much larger quantities of stone must be available. A huge global quarrying and processing industry supplies the polished stone we see all around us. Detective workDecorative rocks can reveal evidence of ancient life forms, and great global processes -- from earthquakes to the formation of great mountain chains. When identifying stones, it helps to understand a little about the geological processes that formed them and gave them their various characteristics. Traditionally, marble is defined as any rock composed of calcite or dolomite (two common carbonate minerals) that takes a good polish. The stone trade still uses this definition, comparing marbles to limestones that have similar compositions but do not take a polish. Modern geologists are much more specific: they classify limestones as sedimentary rocks, and marbles as limestones which have been "metamorphosed" that is, altered -- by heat and pressure. In a similar way, the trade uses the term granite to encompass a wide variety of rock types composed of silica or silicate minerals (but not as specifically as geologists in their definition). This "jungle of names" is explained more fully in the opening "All about decorative stones" section of this book, as are the "earth-shattering" processes by which rocks form, and the broad range of different rock types and how they are classified by the trade and by geologists.This sourcebook describes and illustrates close to 300 decorative rocks and minerals, and introduces many others. This may be just a tiny proportion of the many different kinds used globally, but it includes those that are particularly popular or of special historic interest. The photographs show the stones in actual size, as they appear when polished. Each entry gives a short summary of the stone's source, history and use, and a brief geological descriptPrice, Monica is the author of 'Sourcebook of Decorative Stone An Illustrated Identification Guide', published 2007 under ISBN 9781554072545 and ISBN 1554072549.