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Я́шма, устар. я́спис (тур. jaşim, греч. ἴασπις — пёстрый или крапчатый камень) — плотная скрытокристаллическая горная порода, сложенная в основном кварцем, халцедоном и пигментированными примесями других минералов (эпидот, актинолит, хлорит, слюда, пирит, окислы и гидроокислы железа и марганца), полудрагоценный поделочный камень. Обычно имеет осадочное (иногда вулканогенное) происхождение. Некоторые породы, традиционно относимые к яшмам, богаты полевым шпатом; это либо серые кварц-полевошпатовые роговики, либо кислые эффузивы (порфиры). Среди пород, причисляемых к яшмам, встречаются и почти бескварцевые, богатые гранатом (до 20 % андрадита). В древности под яшмами понимали прозрачные цветные (преимущественно зеленые) халцедоны. Таким образом, химический состав яшмы примерно таков: SiO2 80—95 %; Al2O3 и Fe2O3 до 15 %; CaO 3—6 % (и др.). Для яшм характерны самые разнообразные текстуры: массивная, пятнистая, полосчатая, брекчиевая, плойчатая и др. Наличие множества тонкораспылённых и неравномерно распределённых примесей обусловливает разнообразие и пестроту окраски породы. Однотонные яшмы редки. Jasper, an aggregate of microgranular quartz and/or chalcedony and other mineral phases, is an opaque, impure variety of silica, usually red, yellow, brown or green in color; and rarely blue. The common red color is due to iron(III) inclusions. Jasper breaks with a smooth surface and is used for ornamentation or as a gemstone. It can be highly polished and is used for items such as vases, seals, and snuff boxes. The specific gravity of jasper is typically 2.5 to 2.9. A green variety with red spots, known as heliotrope (bloodstone), is one of the traditional birthstones for March. Jaspillite is a banded-iron-formation rock that often has distinctive bands of jasper. The name means “spotted or speckled stone,“ and is derived via Old French jaspre (variant of Anglo-Norman jaspe) and Latin iaspidem (nom. iaspis) from Greek ἴασπις iaspis (feminine noun),[6] from an Afroasiatic language (cf. Hebrew ישפה yashpeh, Akkadian yashupu).[7] This Semitic etymology is believed to be unrelated to that of the English given name Jasper (of Persian origin). Green jasper was used to make bow drills in Mehrgarh between 4th and 5th millennium BC.[9] Jasper is known to have been a favorite gem in the ancient world; its name can be traced back in Arabic, Persian, Hebrew, Assyrian, Greek and Latin.[10] On Minoan Crete, jasper was carved to produce seals circa 1800 BC, as evidenced by archaeological recoveries at the palace of Knossos. Although the term jasper is now restricted to opaque quartz, the ancient iaspis was a stone of considerable translucency including nephrite.[2] The jasper of antiquity was in many cases distinctly green, for it is often compared to emerald and other green objects. Jasper is referred to in the Nibelungenlied as being clear and green. The jasper of the ancients probably included stones which would now be classed as chalcedony, and the emerald-like jasper may have been akin to the modern chrysoprase. The Hebrew word may have designated a green jasper.[12] Flinders Petrie suggested that the odem, the first stone on the High Priest's breastplate, was a red jasper, whilst tarshish, the tenth stone, may have been a yellow jasper. Яшма с белыми полосами Jasper with white stripes 碧玉的白色条纹 白い縞模様のジャスパー 흰색 줄무늬가있는 재스퍼 يشب مع خطوط بيضاء Jaspis mit weißen Streifen Jaspe à rayures blanches แจสเปอร์มีแถบสีขาว Jaspe con rayas blancas Jasper com listras brancas Jasper con strisce bianche Jasper με άσπρες ρίγες
