How is Gem Black Opal found?
Gem black Opal is found in the formation of a nobby (rounded nodule) or in a seam. Lightning Ridge in Australia is the only sedimentary deposit in the world for Gem Black Opal.
What is the appearance of Gem Black Opal?
Black Opal has a natural dark appearance. The opal has a black potch backing with a colour bar on top of the potch.
Gem Black Opal usually comes in the colours of green, orange & red. The best color is red blue. All of these colours are interchangeable. No two pieces of opal will ever be identical making each piece rare & individual. The most valuable colours are a mixture of red & Prussian blue.
The backing colour of the opal is referred to as the ‘ Body Tone’.
The body tone scale is based on the back color of the opal. The scale goes from N1 for black opal to N9 for light opal.
The body tone scale for Gem Black Opal is from N1-N4.
Why is Gem Black Opal becoming rare?
Gem quality sedimentary deposits of Gem Black Opal are only found in Lightning Ridge, Australia.
Government regulations and the increased costs of maintaining machinery has made the mining of the material expensive for the ‘little guy’. Larger companies are mining the area however the deposit area for opal is limited and large discoveries are minimal.
There is currently only a small amount of rough being offered for sale from the area. With demand for Gem Quality Black Opal exceeding the output of rough it has led to an increase in the price of Gem Black Opal.
In my opinion, it is a unique item and the prices will only further increase in value.