What is this colourless gem?

Hi guys I’m struggling to identify this gemstone.

Test results:
Thermal tester: Pass on certain points of stone ( thermally conductive]
Smart pro tester :
Specific gravity: 3.01
RI: 1.653-1.671

Colourless


stone with dark staining on surface

Impossible to say unless it has some form of crystal shape there is no telling what it could be, thanks

The SG and RI are both dead ringers for Euclase. If you can see any cleavage directions, this would be a positive identification. Magnification should show natural inclusions, and blue or red platelets are common!

Not a very good picture; but from what I can see with a darker center and outer light region… I would think that neither SG or RI are at all reliable indicators. Looks like a weathering rind. Perhaps you could re-post with a close-up of just the mineral.