The name of Opal comes from the Greek Opallos, which means “to see the change of color”.

Opal is made up of tightly packed tiny spheres of silica. It takes about 5 million years for 1 cm thick opal to deposit, which shows how difficult it is formed. More than 90% of the opal on the market are produced in Australia. In 1993, the Australian government listed opal as the national gem of Australia.

The history of opal can be traced back to ancient Roman times. The Romans regarded opal from East Africa as a treasure, calling it the "son of Cupid" which is a symbol of hope and innocence.

The most fascinating thing about opal is the "play-of-color phenomenon". Due to the internal structure, the light is diffracted and then it emits a unique colorful spectrum. Usually, the darker the background color, the more beautiful the play-of-color phenomenon can be brought out, and the value is relatively high.

The most common one is the White Opal. The color is white to milky white with less obvious play-of-color spots. It is a very good opal variety with approachable price.

The next higher price is Crystal Opal which is usually transparent and colorless like clear water. Generally, transparency and play-of-color are the main factors to consider. It should not be gray or foggy. This will directly affect the value of crystal opal.

The next grade is Fire Opal, a flaming orange to red. The fire opal with “play-of-color” is very precious and rare.

Black Opal is the most expensive variety in the opal family. It has a dark blue or dark green, or even darker tones with black appearance. The “play-of-color” looks rich and extraordinarily against the background of the black body. With the swing of light and angle, the color will change wonderfully, and it looks brilliant.

Other Sharing of Collection: Fossil-Belemnite Opal

Belemnites are an extinct group of marine cephalopod which existed during the Mesozoic era, from the Jurassic Period to the Cretaceous Period, similar in many ways to the modern squid, and closely related to the modern cuttlefish. However, the opal fossil is the natural specimen formed by being attached to sandstone, let alone the opal’s value itself. The rare Belemnite opal is a real Precious Treasure.

Fossils Talk

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