What is an Opal ?
The word 'opal' is adapted from the Greek word, ‘opallios’, meaning "to see a change in color". The Greeks thought opal gave power of foresight and prophecy, while the Romans saw opal as a symbol of purity and hope.
Opal is one of the birthstones for October.
The Australian aborigines have a legend that opals were born when Earth's Creator descended to Earth on a rainbow and where his foot first touched the earth the stones around began to sparkle, displaying all the colours of the rainbow.
Each Australian Opal is unique with changing colour. The iridescent colours usually change as the stone is tilted. This is known as the Play-of-colour which is caused by diffraction and interference of light. Precious opal consists of regular arrays of tiny spheres of silica and this play-of-colour depends on the uniformity of size and arrangement of these spheres. Larger spheres produce red colour and the smallest sized spheres produce purple colours.
Opal is a hydrated amorphous silica (SiO2·nH2O), with up to 10% water. On Moh's scale of hardness, opal is 6. As a comparison, Diamonds rate at 10, sapphires rate at 9, pearls rate at 3.
We mainly cut Australian opal, which has often been cited as accounting for 95-97% of the world's supply of precious opal.
Our Australian office is also situated in the world famous opal field – Coober Pedy.
The town of Coober Pedy in South Australia is a major source of opal. The world's largest and most valuable gem opal "Olympic Australis" was found in August 1956 at the "Eight Mile" opal field in Coober Pedy.
