Opal - 'Gem of a thousand lights'

Millions of years ago, when dinosaurs roamed the earth a geological process was taking place where non crystalline silica gel seeped into cracks and void in the sedimentary strata. This process over the eons of time hardened to create the unique and colourful gem, OPAL. There are several versions as to the origins of the name ’OPAL’. Some believe it is derived from the Sanskrit word ‘UPALA’ meaning precious stone. Others believed the Greeks named it ‘OPALLIOS’, meaning a change of colour. It is also said to be a derivation of the Latin word, ‘OPALUS’.

Opal is a very unique stone, no two stones are alike and no other has such a ‘play of colour’. The colours displayed in the stone are due to the arrangement of minute (0.0001mm to 0.0005mm) particles of silica. Where these spheres of silica are irregularly packed there is ‘no play of colour’. The play of colour appears when the spheres are arranged in orderly rows and layers, thus allowing light to pass through and be diffracted at different angles, thus producing a play of colour. The larger spheres display, orange to red colours, while the smaller spheres display green to violet colours.

Another unique feature associated with precious opal is the pattern of colour displayed in the play of colour, such as Harlequin opal (chequered patterns of coloured patches, a rare and highly sort after pattern), Pin fire opal (closely spaced specks of brilliant colour) and Ribbon opal (stripes of brilliant colour) to name but a few of the various types of patterns found in precious opal. These descriptive names relate to the pattern of colour, with some pattern being more common than others.

Opal is found in many parts of the world, but Australia has the best and the world’s largest deposits of precious opal. It is in the arid outback of Australia that opal is mined. Black opal from Lightening Ridge in New South Wales; white opal from Mintabie, Coober Pedy and Andamooka in South Australia; boulder opal from Quilpie and Winton areas of Queensland.

Since the last part of the 19th century, some 130 years ago, miners have worked these areas. Early mining was difficult and done by hand; miners were a hardy breed made tough by the hard living conditions and physical work. Today, miner have mechanical methods of extracting the opal from the ground, never the less, miners are still the same hardy breed they were all those years ago.

Opal was a favourite gem and highly valued by the Romans and Mark Antony was no exception. Nonius, a Roman Senator, preferred to leave his country than surrender his opal ring to Mark Antony. From Roman times onwards thru the centuries opal has always been eagerly sought, as it was considered to bring good fortune. Even Queen Victoria of England was delighted when in the late 1800’s it was announced that opal deposits had been discovered in Australia, Queen Victoria commissioned the royal jewellers to make several pieces of opal jewellery.

The official birthstone for the month of October, it is known as a symbol of hope and health. Today opal is still highly valued, sought for its unique beauty and play of colour. It is truely the gem of a thousand lights.