Gemstones
Opal: Play of Colour Explained
Black, white, boulder and fire opals — how to judge colour play, pattern and durability.
What creates the colour
Microscopic silica spheres diffract light into flashes of spectral colour. Larger spheres produce rare reds.
Doublets and triplets
Thin opal slices glued to backing are cheaper assembled stones. Look at the side profile for a straight glue line.
Verification tools & references
Every Riakoob piece arrives certified, insured and covered by our 12-month value promise.
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