Boulder Opal

Boulder opal is found in the outback regions of Queensland. This material occurs as thin veins in sedimentary ironstone boulders. The colour layer is naturally part of the dense brown ironstone base and is inseparable from it, creating opals with interesting wavy surfaces and freeform shapes, giving boulder a individual look. It is comparatively less expensive than black opal and in recent years has enjoyed an increased popularity. Clifton Opal specializes in Boulder and is the largest boulder opal supplier in Australia.

 

 

Black Opal

Black Opal is from the North Western New South Wales region of Lightning Ridge. Black opal is so named because of the dark backing called potch, or for its dark body colour. The rough is very different in shape to boulder opal rough and forms in seams and small nodules called "nobbies"Black opal tends to be cut into cabochon (domed) shapes, usually in oval form.Again the red opal is the most rare and valuable of the stones.

Light Opal

Light Opal is Is from the South Australian regions of Coober Pedy, Andamooka and Mintabie. Light opal colour ranges from near opaque to translucent and transparent. The more transparent varieties are known to as crystal (this refers to the transparency and not its structure) and are among the most beautiful light opals.Lightning Ridge in New South Wales also produces very desirable crystal opal.

Doublets and Triplets

Triplets and doublets are man made opals formed from layers. These are generally of a lower price than the solid opals.

Triplets : Three layers usually glued together with an epoxy resin.

• Layer 1. Thin slice of black potch or obsidian (volcanic rock) or ironstone.
• Layer 2. Fine slice of crystal or light opal.
• Layer 3. Domed quartz or plastic.

Doublets

• Layer 1. Thin slice of black potch or Obsidian (volcanic rock) or ironstone, as with triplets.
• Layer 2. Well-domed crystal opal glued together.