![]() While these "picture jaspers" can be found all over the world, specific colors or patterns are unique, based upon the geographic region from which they originate. Healed, fragmented rock produces brecciated (broken) jasper. Diffusion from a center produces a distinctive orbicular appearance, i.e., leopard skin jasper, or linear banding from a fracture as seen in leisegang jasper. Picture jaspers exhibit combinations of patterns (such as banding from flow or depositional patterns (from water or wind), dendritic or color variations) resulting in what appear to be scenes or images (on a cut section). A few are designated by the place of origin such as a brown Egyptian or red African. Terms attributed to various well-defined materials includes the geographic locality where it is found, sometimes quite restricted such as "Bruneau" (a canyon) and "Lahontan" (a lake), rivers and even individual mountains many are fanciful, such as "forest fire" or "rainbow", while others are descriptive, such as "autumn" or "porcelain". The classification and naming of jasper varieties presents a challenge. Weathering, with time, will create intensely colored superficial rinds. The original materials are often fractured and/or distorted, after deposition, into diverse patterns, which are later filled in with other colorful minerals. Jasper can be modified by the diffusion of minerals along discontinuities providing the appearance of vegetative growth, i.e., dendritic. Hydrothermal circulation is generally thought to be required in the formation of jasper. Patterns arise during the consolidation process forming flow and depositional patterns in the original silica rich sediment or volcanic ash. Jasper is an opaque rock of virtually any color stemming from the mineral content of the original sediments or ash. (November 2014) ( Learn how and when to remove this template message) 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. The Hebrew word yushphah may have designated a green jasper. 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. Jasper is referred to in the Nibelungenlied as being clear and green. The jasper of antiquity was in many cases distinctly green, for it is often compared to the emerald and other green objects. Īlthough the term jasper is now restricted to opaque quartz, the ancient iaspis was a stone of considerable translucency including nephrite. On Minoan Crete, jasper was carved to produce seals circa 1800 BC, as evidenced by archaeological recoveries at the palace of Knossos. Jasper is known to have been a favorite gem in the ancient world its name can be traced back in Arabic, Azerbaijani, Persian, Hebrew, Assyrian, Greek and Latin. ![]() ![]() Green jasper was used to make bow drills in Mehrgarh between 4th and 5th millennium BC. Hebrew יושפה yushphah, Akkadian yashupu). iaspis)) from Greek ἴασπις iaspis, (feminine noun) from an oriental language (cf. The name means "spotted or speckled stone", and is derived via Old French jaspre (variant of Anglo-Norman jaspe) and Latin iaspidem (nom. Russian, late 19th century, Kremlin Armoury Goat-headed basket carved from red jasper. ![]()
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