They are made up of potch (non precious Opal) and magnificent colors and patterns of precious Opal. They are often referred to as one of the most beautiful gemstones and one of the most significant discoveries of humanity on Earth in recent times.

These types of opals are purchased for investment as their value has seen a steady rise since their initial discovery.  They are also used in high-end jewelry settings. There are two types of black opals found in Lightning Ridge. 

Nobby Opal and Seam Opal

Nobby Opal is the formation of Opal in ball-like shapes, where the Opal is formed inside a ‘nobby’ of potch (colorless Opal). These are often found in clusters in underground mining in Lightning Ridge. 

Seam opal is formed in flat layers between rocks where silica has seeped down over time. It is found in the western area of Lightning Ridge. These types of opals with potch are nontransparent. If you shine light on them, you will not be able to see through the Opal.

The word ‘Black’ does not mean the Opal is dull, dark, or black. Some of the brightest and most beautiful opals are ‘black’. The term refers to the body tone of the stone.

Dark Opal is also found in the same region in Lightning Ridge. They have a dark body tone but not dark enough to be classified as a Black.