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Chalcedony's standard chemical structure (based on the chemical structure of quartz) is SiO 2 (silicon dioxide). Chalcedony has a waxy luster, and may be semitransparent or translucent. It can assume a wide range of colors, but those most commonly seen are white to gray, grayish-blue or a shade of brown ranging from pale to nearly black.
Chrysoprase, chrysophrase or chrysoprasus is a gemstone variety of chalcedony (a cryptocrystalline form of silica) that contains small quantities of nickel. Its color is normally apple-green, but varies from turquoise-like cyan to deep green. The darker varieties of chrysoprase are also referred to as prase.
Chrome chalcedony, raw. Chrome Chalcedony - Greek χρυσόπρασος chrysoprasos, the tenth foundation stone of the celestial Jerusalem (Revelations 21:20). This likely refers to a chrome chalcedony (and not a nickel-colored chrysoprase, as the word is used today), which was known in the Roman world at the time. [7]
Main jade producing countries. Jade is an umbrella term for two different types of decorative rocks used for jewelry or ornaments.Jade is often referred to by either of two different silicate mineral names: nephrite (a silicate of calcium and magnesium in the amphibole group of minerals), or jadeite (a silicate of sodium and aluminum in the pyroxene group of minerals). [1]
Neolithic Age (new stone era) beginning about 10,200 years ago: flint tools (diagenesis of marine microfossils, microcristalline opal and chalcedony), jade tools (usually nephrite, jadeitite or jadeite-jade is less common), kaolin earth (adobe bricks made by drying of clay), copper, gold, silver and rocksalt.
Jade Jade is most commonly associated with the colour green but can come in several other colours as well. Jade is closely linked to Asian culture, history, and tradition, and is sometimes referred to as the stone of heaven. Jasper Jasper is a gemstone of the chalcedony family that comes in a variety of colours.
Agate (/ ˈ æ ɡ ɪ t / AG-it) is a variety of chalcedony, [1] which comes in a wide variety of colors. Agates are primarily formed within volcanic and metamorphic rocks.The ornamental use of agate was common in ancient Greece, in assorted jewelry and in the seal stones of Greek warriors, [2] while bead necklaces with pierced and polished agate date back to the 3rd millennium BCE in the Indus ...
Differences in chemical composition and crystal structure distinguish the various species. Within a mineral species there may be variation in physical properties or minor amounts of impurities that are recognized by mineralogists or wider society as a mineral variety. Mineral variety names are listed after the valid minerals for each letter.