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Blue corundum fluorescence?

Hi everyone,

I have just seen an odd specimen of sapphire and need some advice.
blue Red

Blue in daylight and red under UV. Help?


That is a dramatic change and a beautiful red color. I have seen natural sapphire with red fluorescence under LW uv light. SW uv light might fluoresce yellowish green. Chalky blue or yellowish green could indicate heat treatment. But the red is natural.

Jpe206, thanks for the input. This was the only specimen I’ve ever seen transition so strongly, so I wasn’t sure what that might mean. Thank goodness it’s probably natural!

That is what we call, a critter of another world. Is it a color change Sapphire on steroids? Is it an Alexandrite gone wild? I must say that it is unique and beautiful. I would love to see more of those stones and where did that on come from?
All the best.

Hi Otter,

It only fluoresces under UV, though. It would be amazing if that were its daylight colour!
Origin unknown for now (found it looking through a friend’s old collection). Have sent it for expert appraisal so will keep you all updated when I find out.

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Synthetic spinel