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Stone and Masonry

Construction Rocks

The strongest rock is trap, a very old igneous and siliceous primeval stone that can withstand over 67,000 lb/in2 (3,900 kg/cm2) pressure. Gabbro and basalt are similar. But these rocks are very difficult to work, or quarry. They are not formed in layers and hence are very difficult to layer. Granite is somewhat manageable, and is used where great strength or resistance to weather are needed. But it is difficult to work with and therefore quite expensive. Other qualities of rock that make it more desirable for use in constructions are ease of quarrying, nearness to quarry, durability, resistance to absorbing water, and strength. However, stone masons look mainly for shape (they desire stones more or less square), their proximity, and the price. The stone most often used by masons is sandstone or limestone.

Stone masonry always has stood for permanence. Anything properly made of stone outlasts the same thing made of any other material, even concrete with steel mesh imbedded. But one must be certain of one's work. It can take weeks to repair a mistake. Stone masonry differs entirely from brick or block masonry, where every layer must lie in a straight line, where there must be square and level units and mortar joints that are uniform. The main reasons for building with stone are its beauty, endurance, strength, and mass.

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Science EncyclopediaScience & Philosophy: Stomium to SwiftsStone and Masonry - Stone Types, Chemical Composition, Construction Rocks, Stone Construction, Bricks