OPALANIFine Australian Opal Jewelry

Boulder opal — the ironstone stays, on purpose

Solid Queensland boulder opal rings and pendants. Natural ironstone matrix, never a glued backing.

The dark back is the rock it grew in

This has to come first, because it is the single most misunderstood thing in opal. Boulder opal has a dark backing, and that backing is natural ironstone — the host rock the opal formed inside. It is not glue. It is not a plate. Nobody added it.

A doublet has a dark backing too, and that one is glued on to fake exactly this effect. So the two can look similar in a photograph and are not remotely the same object. A solid boulder opal is one continuous piece of natural stone; a doublet is two pieces and an adhesive. That difference is most of why boulder opal costs what it costs, and it is the reason I'd rather sell a boulder stone than defend a doublet.

Koroit, Winton, Quilpie — the ground makes the pattern

Boulder opal comes from western Queensland, where opal filled the cracks and cavities in ironstone concretions instead of forming in flat seams. Koroit is known for webbed matrix — colour trapped in a lace of ironstone across the whole face. Other fields give cleaner seams with a solid band of colour against a dark back.

Because the opal took the shape of a crack, no two stones can repeat. That is not a marketing line about uniqueness; it is a physical constraint on the material. Every piece names its field where I know it.

The best value in solid Australian opal right now

Per carat, boulder sits well below black opal, and a good deal of that discount is because the ironstone counts in the weight. You are buying real Australian stone, solid, certified, at a fraction of what the same brightness costs on a black body tone.

For a first solid Australian opal — or for a man's ring, where the matte ironstone and the heavier stone both help — it is the piece I'd point at. What the numbers look like across all four types is in the opal price guide.

How I cut it

I cut boulder to the seam, not to a template. The opal is a few millimetres of colour lying in a crack; take too much and it's gone, take too little and the face is dull. So the outline of the finished stone is the stone's decision, and the free shapes you see here are the honest result of following colour rather than tracing an oval.

It also means I can't cut you a matching pair, and I won't pretend otherwise.

Matrix, potch and what counts as a flaw

Ironstone webbing through the face is boulder opal working as designed. Patches of potch — opal with no play-of-colour — are normal in natural stone. Fine sand lines are normal. None of that is a defect, and a stone with a little of its own country in it is doing something a lab-grown one physically cannot.

What is a defect: a fissure through the colour bar that could open. Those don't leave the bench. The distinction is drawn properly in natural imperfections in opal.

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