Black opals are one of the most precious and rarest gemstones in history. They were once considered bad luck, but now they are quite popular with jewellers and people around the world. The popularity of the stone can be attributed to various factors. The most attractive feature is the vibrant show of colours on a dark coloured background.

This most popular gemstone consists of uniform spheres of silica, which form a grid-like structure. The space between the spheres contains silica solution. When light passes through the spheres and hits the liquid, it produces different rainbow hues.

The colour play depends on the size of the spheres and in many cases, its origin also. A smaller round-shaped object results in blue colours, while orange and red will be the result of large spheres. Uniform grid-like structure results in more intense shades.

Few factors that play a huge role in deciding the price of the stone are:

Brightness and brilliance: Many colours flashing from a gemstone would not fetch a price like a gem with a high degree of brilliance. The brightness and hue also play a crucial role.

Colours: If the dominant colours in an opal are red, it attracts a high cost, when compared to other shades. The brightest colour of the rainbow is followed by orange, yellow, green, indigo and violet, in terms of price for an opal. A brilliant violet could gather more price than a dull red.
Patterns: The diffraction of light within opal causes interesting patterns to rise. These patterns, like colour, play a major role to increase or decrease the price. ‘Pinfire’ and small dot-like pattern are less in demand. Stripes, peacock feather shapes, broad brushstroke-like features can gather a huge price. One should note that the pattern change with time.

Some opal may come at a very low price, while others could cost thousands of dollars. It is very important to check the genuineness before making the purchase.

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