Danburite is hardly an everyday gemstone, but this particular example managed to make an uncommon gem somewhat more unusual.
Gem Note: Chatoyant Danburite from Sri Lanka, Journal of Gemmology 2026, Vol 40 (2): 116-117
Author: Charles Evans FGA DGA
At almost 50 ct, this yellow danburite from Okkampitiya, Sri Lanka, displayed something unexpected: a subtle but unmistakable cat’s-eye. Chatoyancy has previously been reported in danburite from Tanzania, but not from Sri Lanka.
That was reason enough to take a closer look. Some fascinating microscopy revealed the culprits: abundant, subparallel needle-like tubes—probably dissolved dislocations—responsible for concentrating reflected light into the chatoyant band. It was also interesting to note what the gem cutter had done to maximize the effect by ‘frosting’ the base to reduce the light passing through and to accentuate the phenomenon.
Sometimes the most interesting stones are simply the ones that do something they are not expected to do!
Gem Note on Coloured Stones, featured in The Journal of Gemmology, Volume 40, No.2, 2026
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