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Chrysoprase
Chrysoprase (also Chrysoprase) is a gemstone variety of chalcedony, (fibrous
form of quartz) which contains small quantities of nickel. Its color is
normally apple-green, but varies from deep green. It is cryptocrystalline
that means that it is composed of crystals so fine that they may not be
seen as distinct particles under normal magnification. This sets it apart
from rock crystal, amethyst, citrine, and also the other varieties of
crystalline quartz which are basically transparent and also formed from
easily recognized six-sided crystals. Other members of the cryptocrystalline
quartz family include agate, carnelian, and also a form of onyx. Unlike
many other non-transparent members of the quartz family, it is the color
is Chrysoprase, rather than any other pattern of markings, that makes
it desirable. The word Chrysoprase comes from the Greek chrysos meaning
'gold' and parson, meaning 'leek'.
Colour and Value
Due to its comparative scarcity and its pleasing green color, Chrysoprase
is one of the most prized varieties of the quartz. Higher quality specimens
often rival fine jade, for which it is sometimes also mistaken. Cut into
cabochons (smooth domed gems with flat backs for use in jewelry), it could
be as sought after as fine amethyst.
Unlike emerald which owes its beautiful green color to the presence of
chromium, the color of Chrysoprase is due to its trace amounts of nickel
in the structure. The nickel reportedly occurs as the platelets of the
talc-like mineral Willamette. Chrysoprase results from the deep weathering
and lateralization of nickeliferous serpentinites or other ultramafic
ophiolite rocks. In the Australian deposits, Chrysoprase occurs as veins
and nodules with its brown goethite and other iron oxides in the magnetite-rich
saprolite below an iron and the silica cap.
As with all forms of quartz, Chrysoprase has a hardness of 6 - 8 on the
Mohs hardness scale and a concordat fracture like flint.
The best known sources of Chrysoprase are Queensland, Western Australia,
Germany, Poland, Russia, Arizona, California, and also Brazil
Chrysoprase Bracelet
Chrysoprase is a gemstone variety of chalcedony (fibrous form of
quartz).....more |
Chrysoprase Earing
Due to its relative scarcity and pleasing green color, Chrysoprase
is one of the most prized varieties of quartz.....more |
Chrysoprase Necklace
Unlike emerald which owes its good-looking green color to the attendance
of chromium.....more |
Chrysoprase Rings
Chrysoprase is careful the most precious stone in the chalcedony
group.....more |
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