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When RI and SG don\'t correspond


having taken the RI reading multimal times of 1.506 this gives me a choice of 3 topaz, beryl or tourmaline.
The SG reading I got was 3.65
The colour of the stone is light pink
Clarity is vvs
I am right in thinking that this could be a synthetic gem


Hi Tony, If you work out the Birefringence of the RI this should directly point to which gemstone you have certainly close enough


Thank you for your reply I will go and do as you say and let you know the results many thanks
Regards Tony