Connecticut State Stone
Brownstone STATUS Unofficial DESCRIPTION Brownstone is the name given to a ferruginous (iron-rich) sandstone quarried at several locations in the northeastern United States. It was fashionable in the 19th century as a facing material for better buildings in many East Coast cities. The brownstone quarried since colonial times in the town of Portland, Connecticut, is reddish brown. Sandstone is one of the clastic sedimentary rocks, formed from the eroded remnants of older rocks. As the name suggests, it is made up of sand, so it falls between siltstone and conglomerates in grain size. The name may suggest a crumbly or impermanent stone, but the best sandstone compares well with granite for hardness and density. Sandstone’s color ranges from white through buff and yellow to red and brown. Brownstone’s color comes from iron oxide (rust). A STATE SYMBOL While Connecticut has not designated an official state stone, the famous Portland brownstone’s economic and historic meaning for the state, as well its contribution to the aesthetic of Connecticut’s cities, suggest it as representative of the state. Middle-class urban houses and public buildings in Portland, Bridgeport, Hartford, and New Haven make substantial use of brownstone, which was quarried commercially along the banks of the Connecticut River beginning in the 1700s and is still produced there today. Brownstone quarrying was a major Connecticut industry during the heyday of the stone, employing 1,500 workers and engaging 25 ships to transport the stone by way of the Connecticut River to Atlantic seaboard cities. The Portland quarries supplied an estimated 80 percent of the stone used in the row houses of New York City. FORMATION Sandstone is a sedimentary rock that forms by accretion (accumulation) of grains of sand. The grains, themselves remnants of much older rocks, typically accrete in layers underwater or in deserts, as well as in glacial outwash. As layers are buried under layers, pressure accumulates, compacting the grains of sand closely. However, the temperatures and pressures to which sandstone is subjected are much lower than those for igneous and metamorphic rocks; the grains of sand do not melt or deform. When dissolved silica or calcium carbonate fills the spaces between the grains, it cements them together, forming the stone. GEOGRAPHIC DISTRIBUTION Sedimentary rocks cover about 80 percent of the earth’s land and most of the ocean floor, yet they form a thin skin, accounting for only eight percent of the volume of the earth’s crust. Sandstone specifically makes up about a quarter of this material. Because it lies at the surface, it is readily available all over the world. The Portland brownstone specifically is part of a formation that stretches in a broken band from Nova Scotia through North Carolina. PRODUCTION In 2005, U.S. quarries sold 192,000 metric tons of dimension (cut in shapes) sandstone in the domestic market, of which roughly one-fourth was rough stone and the rest was dressed stone. Ten tons of U.S. dimension sandstone were sold in Canada. The most important early U.S. brownstone quarries were in Portland, Connecticut; Hummelstown, Pennsylvania; and Basswood Island, Wisconsin. Brownstone, while not experiencing the vogue of the 1800s, is still popular for architectural cladding and is quarried in a few places in the U.S., Europe, and Asia. USES Sandstone is used in architecture because of its beauty, strength, and versatility. Its resistance to erosion and weathering makes it popular for outdoor applications, including foundations, walls, and paving stones; its heat resistance makes it an excellent choice for fireplaces; its resistance to salt air makes it useful for buildings near the sea. The variety of colors, and the interesting striations that occur in some sandstones, give the material great appeal both for structural applications and for carved decorations. In addition, crushed sandstone is a source of silica for the manufacture of glass. Poorer quality stone may be crushed to make a component of concrete. FAMOUS EXAMPLES Stonehenge, the Neolithic astronomical monument, is built of massive sandstone pillars. The Great Sphinx is among Egypt’s ancient monuments made of sandstone. In China, the Great Buddha at Leshan is carved out of a red sandstone rock face. The entire village of Collonges-la-Rouge, in Limousin, France, is built of red sandstone; a popular tourist attraction, the picturesque village was designated a historical monument in 1942. Natural monuments are also made of sandstone; the most famous example may be the eroded mesas of Monument Valley in Utah and Arizona.	Brownstone Cliff Brownstone Sample Large Brownstone Boulder Brownstone Used for Buildings Brownstone Archway with Marble Insert BROWNSTONE FACTS Name: Brownstone Chemical Formula: SiO2 Color: Varying shades of reddish-brown
	Author: World Trade Press