The Story Behind Australian Opals
Australian opals have a story unlike almost any other gemstone. Their colour is not caused by pigment, but by light passing through tiny spheres of silica within the stone. When these spheres are arranged in the right way, they split white light into flashes of red, green, blue, orange and violet – the famous “play of colour” that makes opal so distinctive.
Australia became the world’s most important source of precious opal in the early twentieth century, but the story began earlier. Commercial opal mining developed in Queensland in the 1870s, followed by White Cliffs in New South Wales in 1889. White Cliffs became one of Australia’s most important early opal fields and is especially relevant when looking at antique jewellery from the late Victorian and Edwardian periods.
Lightning Ridge, also in New South Wales, later became famous for black opal. Although opal was found in the area in the late nineteenth century, its major reputation grew in the early twentieth century. This is important when dating antique pieces: a piece described as Victorian black opal should always be considered carefully, as the strongest commercial association between Lightning Ridge and black opal belongs mainly to the twentieth century onward.
South Australia then became central to the opal story. Coober Pedy was discovered in 1915 and became one of the great white opal fields. Andamooka followed in 1930, producing crystal, white and matrix opal, while Mintabie became known for black, crystal and white opal. Queensland is especially associated with boulder opal, where the opal is cut with its natural ironstone host rock still attached.
These old fields matter to collectors because antique and vintage opal jewellery is often closely linked to the mining history of the stone. A late Victorian or Edwardian jewel set with white or crystal opal may fit well with the early White Cliffs period. A fine black opal in an Art Nouveau, Edwardian or later jewel may suggest the rise of Lightning Ridge material. Mid-century pieces may contain opals from Coober Pedy, Andamooka, Mintabie or Queensland, depending on the colour, type and cutting style.
When buying antique or vintage Australian opal jewellery, the most important thing to look for is the quality of the play of colour. The best stones show bright, lively flashes from different angles. Red is traditionally one of the most desirable colours, especially when seen with orange, green, blue or violet. Large, distinct patches of colour are often more highly prized than very fine scattered pinfire, although beauty is always individual to the stone.
Condition is just as important. Opal is softer than diamonds, sapphires or rubies, so old opals should be checked carefully for chips, cracks, pits and “crazing”, which is a network of fine surface cracks. A well-preserved antique opal can be extremely beautiful, but damage can affect both value and wearability.
It is also important to know whether the opal is solid or assembled. A solid opal is a single natural piece of opal. A doublet is a thin slice of opal attached to a darker backing, while a triplet has a thin opal layer with both a backing and a protective clear top. Doublets and triplets can still be attractive and period-correct in vintage jewellery, but they should always be described honestly and valued differently from solid opals.
The setting can also tell part of the story. Antique opals were often cut as cabochons to show their colour across a domed surface. Some older stones have slightly irregular outlines because cutters tried to preserve as much of the natural colour bar as possible. A handmade gold or platinum setting, good claws, old-cut diamonds, enamel work or Art Nouveau styling can all add to the character of an opal jewel.
Australian opals remain loved because no two are exactly alike. Each stone has its own pattern, colour, brightness and personality. In antique and vintage jewellery, that individuality is even more appealing: the opal is not only a gemstone, but a small piece of mining, geological and design history.