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")
Economy of Sheffield public, such as the Abbeydale Industrial Hamlet and the Kelham Island Museum. Northwest of the city lies Wortley Top Forge, which was a heavy ironworks of international renown. It is a site of historical and industrial importance, contributing to Sheffield's reputation for manufacturing high-quality, precision steel goods, though actually it is located within the boundaries of neighbouring Barnsley. This is a chart of trend of regional gross value added (GVA) of Sheffield at current basic prices published (pp. 240–253) by "Office for National Statistics" with figures in millions of British Pounds Sterling. The city spearheaded the knowledge advances which gave