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What is Stone? Rock is stone before it is moved from where it is found. Stone is rock removed from its bed for use. After rock is taken from quarry and mechanically dressed, meaning it is shaped or squared on one or more surfaces, it is referred to as dimensional stone. 1 History In addition to being used as a structural material throughout human history, stone has been an important interior material. The huge stone columns of the temple at the Karnak in Egypt (begun 1505 BC) support stone lintels over relatively small spans. Between 532 and 537 CE, the Byzantine church of Hagia Sophia in what is now Istambul, Turkey, was designed by two mathematicians, Anthemius of Talles and Isidore of Miletus. The interior of Hagia Sophia was embellished with marbles in many colours, and purplish-red porphyry, reddish-brown carnelian, multi-coloured Onyx (Quartz), Nacre (mother-of-pearl), and ivory inlays. 2 The interior of Hagia Sophia .1 6	Gothic churches are stone structures with complex metal grilles and gates, and carved stone screens, alters, and tombs.3 Early Islamic stone and mud brick architecture preserved older structures within new construction, or build new buildings with parts of old ones Binggeli, pg. 53.4 Man has been using stone as an exterior and/ or interior building materials; creating objects, ornaments, art from stone ever since he found he could shape it by striking a softer stone with a harder one. Stones are grouped in three different types of rock: igneous, sedimentary, and metamorphic. " Porphyry head, 4th cent. 2 The ambulatory at the Abbey of Saint-Denis. 3 7	Types	  of	  Stone	Igneous | the characteristics of these rocks are result of the ways of their formation. Igneous rocks are formed deep in the earth, under the intense heat of volcanic action, magma was forced up through the older solid rock. It then cooled. In result stone types such as Granite, Basalt, and Diorite are formed. 5 Granite | is made of quartz crystals and rock forming minerals which contain silica. Granite is considered one of the hardest stones and is very difficult to carve. Yet ‘carving’ is not the right word for stone; however, it could be used for materials such as limestone or marble, where we can pulverize the stone, trying to break off chips of crystals. Diamond saws and cup grinders would be good tools to cut through granite easily, and to speed up the carving and finishing process. Granite comes in a wide variety of colors, and the crystal size can vary from large and coarse to very fine and dense. Granite takes a high polish and holds up very well outdoors. 6 Igneous Rocks Begin as Magma. 4	Sedimentary | The second category of stones are the sedimentary stones. They form when rocks begin to wear down from wind, rain, and sun, the particles were washed into low lying areas where the sediment accumulated. For instance, in the sea, small plant and animal forms died and drifted to the bottom, adding to the sediment. Over thousands of years, the pressure of these layers cemented the sediment onto limestone (which is formed on the sea floor from sediment and the bodies of primitive sea creatures); or even sandstone. That’s why we can still find small fossils such as crynoids and braciopods in the stone. 7 8	Limestone | is composed primarily of the mineral calcite, or calcium carbonate. While Limestone does not have the natural beauty of the more colourful stones, it has a wide variety of textures	that bring ring the stone to life. Limestone can be polished, but the polish will not last long outdoors. Limestone seems to survive acid rain better than marble, so is a good choice for exterior uses such as outdoor sculptures. 8 Metamorphic | The third category of stones are the Metamorphic rocks that are formed when a sedimentary layer is exposed to heat and pressure and undergoes a chemical change which forms a new crystalline material. 9In result of this process, metamorphism, materials such as limestone become marble. Marble | has been the most preferred stone for interior use since the time of the ancient Greeks. Marble is moderately hard to work with, however it is very durable and holds very fine detail. Marbles from all around North America come in over 250 colours. When brought to a high polish, its crystalline structure sparkles. It does not hold up well outdoors. Acid rain begins to deteriorate the surface within a few years. 10 The image has been made at Zion National Park, Utah, U.S.A., and shows sandstone made of "fossilized" Triassic sand dunes that has weathered into bizarre shapes. These rocks consist almost entirely of quartz. 6 Marble Greek Column. 7 9	What is Concrete? Dictionary describes concrete “as an artificial stone-like material used for various structural purposes. It is made by mixing cement and various aggregates, such as sand, pebbles, gravel, shale, etc. with water and allowing the mixture to harden by hydration.11 Concrete is everywhere; roads, sidewalks, houses, bridges, skyscrapers, pipes, dams, canals, and even nuclear waste containment all are made out of concrete. Concrete is a strong, inexpensive, plentiful material, which is also easy to make. But more importantly, concrete is a flexible material that can be molded to just about any shape. Moreover, it is friendly to the environment because it is virtually all natural, therefore it’s recyclable as well. Known as the most frequently material used in construction, more than a ton of concrete is produced every year for each person on the planet, which comes to approximately 6 billion tons per year. By weight, one-half to two-thirds of our infrastructures, such as roads, bridges, sewers, dams, canals, etc. are made of concrete.12 Don Valley Parkway.9 Toronto City Hall.8 10	Raw State Concrete is a composite material which is made up of a filler and a binder. The binder, which is the cement paste, is made up of cement (a mixture of compounds made by burning limestone and clay together at very high temperatures ranging from 1400 to 1600 ̊C.) and water, while the filler can be fine or coarse aggregate. The cement paste “glues" the filler together to form a synthetic mixture.13 (cement + water) + aggregate = concrete OR sand + cement paste = mortar mortar + gravel = concrete A flow diagram of Portland Cement production.9 11	Time	  Line	3000 BC Egyptians | The Egyptians used lime and gypsum cement.14 300 BC-476 AD | Applian Way, Roman baths, the Colosseum and Pantheon used Pozzalana cement. Animal fat, milk and blood were used as admixtures.15 1793 | British engineer, John Smeaton made the first modern concrete, or the hydraulic cement, by adding pebbles as a coarse aggregate and mixing powered brick into the cement. 1824 | English inventor, Joseph Aspdin invented Portland Cement, which has remained the dominant cement used in concrete production. Joseph Aspdin created the first true artificial cement by burning ground limestone and clay together. The burning process changed the chemical properties of the materials and Joseph Aspdin created a stronger cement than what using plain crushed limestone would produce.16 1836 | The first systematic tests of tensile and compressive strength took place in Germany. 1867 | Joseph Monier of France reinforced William Wand's (USA) flower pots with wire ushering in the idea of iron reinforcing bars (re-bar). 1886 | The first rotary kiln was introduced in England to replace the vertical shaft kilns. 1889 | The first concrete reinforced bridge is built.