翻訳と辞書 Words near each other ・ Pitchin Can ・ Pitching machine ・ Pitching moment ・ Pitching pennies ・ Pitching position ・ Pitching Sacred Harp music ・ Pitching wedge ・ Pitchipoi ・ PitchMen ・ Pitchnut ・ Pitcho Womba Konga ・ Pitchoff Mountain ・ Pitchout ・ Pitchshifter ・ Pitchshifter discography ・ Pitchstone ・ Pitchstone Publishing ・ Pitchy patchy ・ Pitco, California ・ Pitcock ・ Pitcombe ・ Pitcombe Down ・ Pitcoudie ・ Pite River ・ Pite Sami language ・ Pite van Biljon ・ Pite-Rönnskär ・ Piteado ・ Piteco – Ingá ・ Piteglio Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Pitchstone ： ウィキペディア英語版 Pitchstone Pitchstone is a dull black glassy volcanic rock formed when a felsic, viscous lava or magma cools quickly. It is similar to obsidian but is defined by the International Union of Geological Sciences as having a higher water content.〔 It is a volcanic glass, however, unlike a glass pitchstone has an irregular, hackly fracture not a conchoidal fracture, this is due to its coarser (than obsidian) crystal structure. pitchstone has a resinous lustre, or silky in some cases, and a variable composition. Its colour may be mottled, streaked, or uniform brown, red, green, gray, or black. It is an extrusive rock that is very resistant to erosion. The pitchstone ridge of An Sgùrr on the Isle of Eigg, Scotland, was possibly formed as a lava flow in a valley. Pitchstone from the Isle of Arran was used as the raw material for making various items from the Mesolithic through the Neolithic to the Early Bronze Age.〔 Mesolithic use appeals to have been limited to the Isle of Arran itself while in later periods the material or items made from it were transported around Britain.〔 〕 ==References== 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「Pitchstone」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.