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The Langdale axe industry is the name given by archaeologists to specialised stone tool manufacturing centred at Great Langdale in England's Lake District during the Neolithic period (beginning about 4000 BC in Britain). The existence of a production site was originally suggested by chance discoveries in the 1930s, which were followed by more systematic searching in the 1940s and 1950s by Clare Fell and others. The finds were mainly reject axes, rough-outs and blades created by knapping large lumps of the rock found in the scree or perhaps by simple quarrying or opencast mining. Hammerstones have also been found in the scree and other lithic debitage from the industry such as blades and flakes. The area has outcrops of fine-grained greenstone or hornstone suitable for making polished stone axes. Such axes have been found distributed across Great Britain.〔Rodney Castleden, 〕 The rock is an epidotised greenstone quarried or perhaps just collected from the scree slopes in the Langdale Valley on Harrison Stickle and Pike of Stickle. The nature and extent of the axe-flaking sites making up the Langdale Axe Factory complex are still under investigation. Geological mapping has established that the volcanic tuff used for the axes outcrops along a narrow range of the highest peaks in the locality. Other outcrops in the area are known to have been worked, even on Scafell Pike where rough-outs have been found in scree slopes just below the peak at and above the 3000-foot level. ==Petrographic analysis== Archaeologists are able to identify the unique nature of the Langdale stone by taking sections and examining them using microscopy. The minerals in the rock have a characteristic pattern, using a method known as petrography. They have been able to reconstruct the production methods and trade patterns employed by the axe makers. The Langdale industry produced roughly hewn (or so-called "rough-outs") axes and simple blocks. The highly polished final product were usually made elsewhere, such as at Ehenside tarn in the western fringes of the Lake District, and all were traded on throughout Britain and Ireland. The Langdale tuff was among the most common of the various rocks used to make axes in the Neolithic period, and are known as Group VI axes. Flint was also commonly used to make polished axes, and mined at several places, but especially at Grimes Graves and Cissbury, and in continental Europe at Spiennes in Belgium, and Krzemionki in Poland. Polishing the rough surfaces will have improved the mechanical strength of the axe as well as lowering friction when used against wood. Fractures occur more easily in brittle materials like stone when rough owing to the stress concentrations present at sharp corners, holes and other defects in the axe surface. Removing those defects by polishing makes the axe much stronger, and able to withstand impact and shock loads from use. Sandstone was usually used for polishing axes, and whetstones have been found nearby at Ehenside tarn, for example where the rough-outs were polished. Large fixed outcrops were also widely used for polishing, and there are numerous examples across Europe, but relatively few in Britain. That at Fyfield Down near Avebury is an exception, but there must be many more awaiting discovery and publication. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Langdale axe industry」の詳細全文を読む スポンサード リンク
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