Black Opal pendant Sterling Silver Lightning Ridge Australia.
Mined at Lightning Ridge, New South Wales (2).
Size of pendant: 15mm (h) plus 4mm bail x 8mm (w) x 3mm (d).
Sterling Silver hammered trace chain included.
Both pendant and chain are hallmarked 925.
OPAL "the play of light" showing a vast array of all the colours of the rainbow.
Opal is unique and strikingly beautiful.
Tilt and rotate the gem to change the direction of light hitting the stone; the colour will change or disappear.
BLACK OPAL is the most valued and rare.
They have a dark body tone that enables greater refraction and reflection of light, enabling the brightness of colour for which they are known.
The creation of opal is so unique requiring a special series of specific geological, climatic and biological elements to coincide to enable the formation of this elusive gem.
It is only found in a few places and Australia's central desert regions account for around 90% of the supply.
The formation of opal extends back to the Cretaceous period 145 to 65 million years ago.
Black opal are fossil replacements of corals or sponges ☼
During that period the interior of Australia was made up of an inland sea.
Towards the end of this era, the water receded and refilled many times for many aeons.
A silica rich solution flowed into voids and cracks in the ground where the opal forms.
Decomposed organic matter of animals and plants laid down into the sediment create fossilised opal.
This is a very slow process taking 5 million years to form a 1cm or 0.4" thick vein.