Diamonds

Turquoise
For over 3,000 years, the ancient Persians exported turquoise to the world people couldn't get enough of it

Precious Black Opal
Black opal has a dark background, which can be dark grey, dark blue, dark green or grey-black - the darker the

Spectrolite
This is the trade name of Finnish labradorite. Its properties are the same, but it tends to have a dark, opaque colour

Boulder Opal
Boulder opal is precious opal that has a sandstone or ironstone base.

Malachite
Malachite was so popular in the 19th century that the Russian royal family panelled whole rooms with it, and the

Faceted Square Cuts
The second group of faceted cuts includes straight-sided girdle shapes: squares, rectangles, octagons, triangles,

Faceted Round Cuts
There are two main categories of faceted stones: round shapes and straight-sided shapes.