Gahnospinel lovers?

Gem Related Discussion
1

I was looking about the Gahnospinel market & value but couldn’t able to find. Highly appreciated if anybody out there can shed some light about the relevant facts.

2

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4.97 carat, Sri Lankan Origin, Violetish Green Blue, Rare Spinel

3

This can be difficult to identify because it produces a wider range of R.I. and SG. than regular spinels.

4

True, this stone has 1.725 RI. Where normal spinel has 1.718

5

Have you seen this on the IGS website?

Seems to cover your question.