Back to IGS | FAQ | Contact

What is this gemstone?

I am finding it quiet hard to identify this gemstone. Giving me an double RI reading of 1.723-1.745 and an SG of 3.39. Consists of a black and red orange crystal. The black crystal part shines green under a gem torch

I wish I could help but no cigar.

Without knowing much more, i would postulate that the crystal could be a specific type of chrome tourmaline called a dravite.

The phenomenon that is being displayed when you shine light through is called the usambara effect.

For more information, read this article: The Usambara Effect, Color Change and Color Shift.

The pictures do not show enough to help.