Australian Opal

Australia is synonymous with opal, producing approximately 95% of the world’s precious opal. Revered for its mesmerizing play-of-colour, the Australian opal boasts a spectrum of colours, ranging from deep blues and greens to fiery reds and yellows, all depending on the stone’s composition, structure, and the angle of observation. Types of Australian Opals: Black Opal:…

Details

The Opal Fields

The major outcrops of opal an ancient inland sea (known as the Eromanga Sea). The important mining areas in Australian opal production over the last century have been White Cliffs, the Queensland fields, Lightning Ridge, Grawin, Glengarry, Coober Pedy, Andamooka, Mintabie and Lambina. White Cliffs Commercial mining commenced in the late 1880s at the White…

Details

The Rainbow Gem – Colours in Opal

Precious Opal is composed of minute uniform spheres of silica, which are arranged together in orderly three-dimensional grid. The spaces between these spheres contain silica in solution. However, in common opal, where there is no play of colour the spheres are varying sizes and are not uniformly stacked. White light passes through the transparent sphere…

Details

Testimonial March 2023

Highly recommend Cosmopolitan Jewellers. I purchased several pieces of opal and pearl jewelry from overseas using the internet and email to view and select the jewelry. Jenny has been extremely helpful with videos and prompt response to all my questions. The transaction and shipment went smoothly. The jewelry is the highest quality and exceeded my…

Details

Water in Opal

Opal is a hydrous silica composed of predominantly silicon dioxide and water. The chemical composition of opal Is normally described by the general formula SiO,.nH,O. The formula indicates that opal contains water and the value of ‘n’ is variable so the water content is variable and is known to range widely. Such a simple formula…

Details

October Birthstone – Opal

Throughout history Opal has been regarded as the stone of good fortune.  Late in the 19th and early in the 20th century, for commercial reasons, there was a proliferation of damaging reports that opal as an unlucky stone. These were based upon a misinterpretation.  In Roman times the gem was carried as a good luck…

Details

Opal Curiosities

Opal is Australia’s National Gemstone, with each of Australia’s major opal fields having its own distinctive geology, opal types, fossils, landscape, natural and cultural heritage. This panoply of treasures, unique in the world, is the consequence of a freakish combination of geological conditions (Rey 2013). Gemstone laboratories and industry participants, educators and opal enthusiasts look…

Details

Valuing Australian Opal

There is no governing body which has sent the prices for opal; they are the result of what the international market is prepared to pay in order to obtain the gem. As with any other commodity, opal is subject to the laws of supply and demand. The supply opal is never guaranteed – the lack of…

Details

Five Virtues of South Sea Pearls

There are five virtues of fine Pearls that define their value; Lustre, Size, Shape, Complexion and Colour. Lustre Lustre is the paramount characteristic of pearl quality that is instantly noticeable. It is not only how light reflects from Pearl’s surface, but also how it seems to glow from within.  Like all virtues, the lustre of…

Details