This is a natural untreated piece of rough mined in West Australia.We have lightly faced one side with a 180 grit wheel to expose the colour but like all rough there is a gamble here. You can see tumbled and polished stones in our sister sites Sedagems and Mineral gem world which came from the same parcel.
Weight 225.2 cts app
Size 50X39X21 mm app
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 to deep
green. The darker varieties of chrysoprase are also referred to as prase.
(However, the term prase is also used to describe chlorite-included quartz, and
to a certain extent is a color-descriptor, rather than a rigorously defined
Chrysoprase is cryptocrystalline, which means that it is
composed of crystals so fine that they cannot be seen as distinct particles
under normal magnification. This sets it apart from rock crystal, amethyst,
citrine, and the other varieties of crystalline quartz which are basically
transparent and formed from easily recognized six-sided crystals