4 : OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites,
bismuthites, sulfites, selenites, tellurites, iodates)
D : Metal: Oxygen =
1:2 and similar
A : With small cations: Silica family
Chlorite, Epidote, Feldspars, Fluorite, Micas, Zeolites,
many other species.
a translucent, apple-green variety of Chalcedony which
is a type of cryptocrystaline, or fine-grained, Quartz
with a fibrous microstructure. Chrysoprase is colored shades
of green by the presence of nickel (N). It is always
translucent, never fully transparent and usually found as cabochons but
may also be faceted. It is a very attractive material
with an almost unique color in the gem world. Because
of its color and typical source, Chrysoprase has also
been called Australian Jade.
is found mostly in Australia at Nundle, New South Wales
and Marlborough, Queensland; but also found in Brazil
at Goiás, Central-West Region and Bahia, Northeast Region and
Minas Gerais, Southeast Region. Lesser known sources
are Szklary, Zabkowice (Frankenstein),
Zabkowice District, Lower Silesia, Poland; Kuruman, Northern Cape Province, South Africa;
La Paz County, Arizona, USA and Newfane, Windham County, Vermont, USA.