wrought iron

One of the two forms in which iron is obtained by smelting. Wrought iron is a soft, easily worked, fibrous metal. It usually contains less than 0.1percnt carbon and 1–2percnt slag. It is superior for most purposes to cast iron, which is hard and brittle because of its higher carbon content. In antiquity, iron was smelted directly by heating ore in a forge with charcoal, which served both as fuel and reducing agent. While still hot, the iron-and-slag mixture was removed as a lump and worked (wrought) with a hammer to expel most of the slag and weld the iron into a coherent mass. Wrought iron began to take the place of bronze (being far more available) in Asia Minor in the 2nd millennium BC; its use for tools and weapons was established in China, India, and the Mediterranean by the 3rd century BC. Later, in Europe, wrought iron was produced indirectly from cast iron (see puddling process). With the invention of the Bessemer process and open-hearth process, steel supplanted wrought iron for structural purposes, and its use in the 20th century has been principally decorative.

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Most common type of anemia, which may develop in times of high iron loss and depletion of iron stores (e.g., rapid growth, pregnancy, menstruation) or in settings of low dietary iron intake or inefficient iron uptake (e.g., starvation, intestinal parasites, gastrectomy). Much of the world's population is iron-deficient to some degree. Symptoms include low energy level and sometimes paleness, shortness of breath, cold extremities, sore tongue, or dry skin. In advanced cases, red blood cells are small, pale, and low in hemoglobin, blood iron levels are reduced, and body iron stores are depleted. Treatment with iron usually brings quick improvement.

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Metallic chemical element, one of the transition elements, chemical symbol Fe, atomic number 26. Iron is the most used and cheapest metal, the second most abundant metal and fourth most abundant element in Earth's crust. It occurs rarely as a free metal, occasionally in natural alloys (especially in meteorites), and in hundreds of minerals and ores, including hematite, magnetite, limonite, and siderite. The human body contains about one-sixth of an ounce (4.5 g) of iron, mostly in hemoglobin and its precursors; iron in the diet is essential to health. Iron is ferromagnetic (see ferromagnetism) at ordinary temperatures and is the only metal that can be tempered (see tempering). Its uses in steels of various types, as well as in cast and wrought iron (collectively, “ferrous metals”), are numerous. Alteration of its properties by impurities, especially carbon, is the basis of steelmaking. Iron in compounds usually has valence 2 (ferrous) or 3 (ferric). Ferrous and ferric oxides (FeO and Fe₂O₃, respectively) are used as pigments and the latter as jewelers' rouge. Rust is ferric oxide containing water; ferric oxide is widely used as a magnetic recording material in computer data-storage devices and magnetic tapes. Ferrous and ferric sulfates and chlorides are all of industrial importance as mordants, reducing agents, flocculating agents, or raw materials and in inks and fertilizers.

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Alloy of iron that contains 2–4percnt carbon, along with silicon, manganese, and impurities. It is made by reducing iron ore in a blast furnace (cast iron is chemically the same as blast-furnace iron) and casting the liquid iron into ingots called pigs. Pig iron is remelted, along with scrap and alloying elements, in cupola furnaces and recast into molds for a variety of products. In the 18th–19th centuries, cast iron was a cheaper engineering material than wrought iron (not requiring intensive refining and hammering). It is more brittle and lacks tensile strength. Its compressive (load-bearing) strength made it the first important structural metal. In the 20th century, steel replaced it as a construction material, but cast iron still has industrial applications in automobile engine blocks, agricultural and machine parts, pipes, hollowware, stoves, and furnaces. Most cast iron is either so-called gray iron or white iron, the colours shown by fracture; gray iron contains more silicon and is less hard and more machinable than white iron. Both are brittle, but malleable cast iron (produced by prolonged heat-treating), first made in 18th-century France, was developed into an industrial product in the U.S. Cast iron that is ductile as cast was invented in 1948. The latter now constitutes a major family of metals, widely used for gears, dies, automobile crankshafts, and many other machine parts.

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Final technological and cultural stage in the Stone–Bronze–Iron-Age sequence (or Three-Age System) in which iron largely replaced bronze in implements and weapons. The start of the Iron Age varied geographically, beginning in the Middle East and southeastern Europe circa 1200 BC but in China not until circa 600 BC. Though the large-scale production of iron implements brought new patterns of more permanent settlement, use of iron for weapons put arms in the hands of the masses for the first time and set off a series of large-scale movements and conquests that did not end for 2,000 years and that changed the face of Europe and Asia. Seealso Bronze Age.

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Ferrum is a census-designated place (CDP) in Franklin County, Virginia, United States. The population was 1,313 at the 2000 census. Ferrum is home to Ferrum College and its Blue Ridge Folklife Festival. It is part of the Roanoke Metropolitan Statistical Area.

Geography

Ferrum is located at (36.926381, -80.011181).

According to the United States Census Bureau, the CDP has a total area of 9.2 square miles (24.0 km²), all of it land.

Demographics

As of the census of 2000, there were 1,313 people, 285 households, and 169 families residing in the CDP. The population density was 141.9 people per square mile (54.8/km²). There were 307 housing units at an average density of 33.2/sq mi (12.8/km²). The racial makeup of the CDP was 80.81% White, 16.22% African American, 0.23% Native American, 0.69% Asian, 0.91% from other races, and 1.14% from two or more races. Hispanic or Latino of any race were 1.68% of the population.

There were 285 households out of which 32.6% had children under the age of 18 living with them, 48.8% were married couples living together, 6.7% had a female householder with no husband present, and 40.4% were non-families. 33.0% of all households were made up of individuals and 7.7% had someone living alone who was 65 years of age or older. The average household size was 2.38 and the average family size was 3.07.

In the CDP the population was spread out with 13.6% under the age of 18, 53.4% from 18 to 24, 17.2% from 25 to 44, 11.2% from 45 to 64, and 4.6% who were 65 years of age or older. The median age was 21 years. For every 100 females there were 122.2 males. For every 100 females age 18 and over, there were 131.0 males.

The median income for a household in the CDP was $35,208, and the median income for a family was $46,818. Males had a median income of $27,938 versus $22,917 for females. The per capita income for the CDP was $12,276. About 4.0% of families and 9.7% of the population were below the poverty line, including none of those under the age of eighteen or sixty-five or over.

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