SPECTRA

Stone Guide

Opal

Origin: Australia (Lightning Ridge, Queensland, Coober Pedy)

What Makes It Special

A top-tier opal is hypnotic. The play of color, or 'fire', is caused by the diffraction of light crashing through microscopic silica spheres inside the stone. Australia produces about 95% of the world's finest opals, with Lightning Ridge black opal sitting comfortably at the pinnacle. Ancient opals found in Victorian jewelry are extraordinarily beautiful—the Victorians had a deep reverence for them.

Required Documentation

⚠️GIA
⚠️AGL
Appraisals for doublets without clear disclosure

Opals are evaluated heavily on visual impact. Lab reports are useful to confirm a piece is a natural solid opal rather than an assembled doublet or triplet.

Price Guide 2026

Fine Black Opal
$500–$5,000/ct
Solid stone with nice play of color.
Exceptional Black Opal
$5,000–$30,000/ct
Dark body tone with brilliant, flashing multi-color fire.

⚠️ Assembled opals (doublets and triplets) are worth a fraction of the price of solid natural opal. Ethiopian opals (often treated or unstable) are also priced much lower. Natural solid Australian material is what matters.

Notable Auction Records

The Virgin Rainbow (Bellem)

Museum Valuation

Over $1,000,000

N/A

Dealer's Notes

1

Always confirm you are buying a SOLID natural opal. Doublets (a thin slice glued to a backing) have their place in budget pieces, but not in serious jewelry.

2

For black opals, assess the body tone. The darker the background, the more impressively the colors 'pop'.

3

Red fire is the rarest and most valuable flashing color, followed by orange, yellow, green, and blue.

4

Ethiopian opal has flooded the market and is very affordable, but it absorbs water (hydrophane) and can lose its color. Stick to true Australian stones.

5

Take particular note of 'harlequin' or 'broad flash' color patterns, which are prized far above tiny 'pinfire' patterns.

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