Sapphire — specimen 0364, photo © NMNHS
Weight: 0.12 ct; size: 2.92 | 2.89 | 1.97 mm; shape: round; colour: colourless; clarity: eye clean; cut: good; treatment: heating.
Very clean specimen; good brilliant style cut.
More information from ‘Classification’
Most commonly refers to a blue gem variety of corundum, but other coloured varieties of corundum are also described as sapphire, except the natural red.