出典:Wiktionary
From a Cornish word,[3] perhaps Cornish elven, elvan (“spark”)[4][5] because the hard rock could be struck to spark fire.[6]
elvan (comparative more elvan, superlative most elvan)
elvan (countable かつ uncountable, 複数形 elvans)
elvan (comparative more elvan, superlative most elvan)
出典:Wikipedia
出典:『Wikipedia』 (2011/02/28 23:04 UTC 版)
Elvan is a name used in Cornwall and Devon for the native varieties of quartz-porphyry. They are dispersed irregularly in the Upper Devonian series of rocks and some of them make very fine building stones (e.g. Pentewan stone, Polyphant and Catacleuse stone). Greenstone is another name for this stone and it is often used for parts of buildings such as doorways so they can be finely carved. Most of the elvan quarries are now disused. Others are quarried in bulk for aggregates commonly used for road-building.