Geography of Sheffield county, from bituminous (ideal for domestic heating) to "Thick Coal", of a semi-anthracitic quality, appropriate for use in iron-smelting and in engine furnaces. Associated with the Upper Coal Measures were valuable iron ore deposits, occurring in the form of nodules. Large quantities of locally occurring fireclay were also exploited, as well as ganister (a clay used to make refractory furnace linings). The city of Sheffield derives its name from the River Sheaf which Until the 17th century was written as "Scheth" or "Sheath". Sidney Oldall Addy equates the origins of this word with the Old English "shed" (as in "water-shed")
Sheffield City Council elections Sheffield City Council elections Sheffield City Council elections usually take place by thirds, three years out of every four. Each of Sheffield's 28 wards is represented by three positions on the council, meaning there are usually 28 seats contested in each local election. 2004 saw new ward boundaries and therefore all seats were contested. Before 1974, elections were by thirds annually for a three-year term, with Aldermen elected from the body of councillors every three years. In 1974, Aldermen were abolished, and elections to Sheffield City Council are by thirds, in three years of every four, for a four-year term.