Back to IGS | FAQ | Contact

Fluorescent tanzanite?

Has anyone seen tanzanite fluoresce bright Orange red? Trying to identify a stone previously sold as a Tanzanite but I couldn’t get a RI reading in it.

Tanzanite rarely sees orange-red fluorescence.
You have to be careful, it may be synthetic blue spinel (cobalt), which will also show red fluorescence under short-wave ultraviolet.
It is recommended to confirm the refractive index of the gemstone first before making a diagnosis.

Thank you for responding, I was unable to get a reading with RI due to the mounting of the stone. That makes sense however, thanks again.