A rough, unpolished sapphire.
A polished sapphire.
After a stone is sawed and ground to the desired shape, it is polished to a mirror-like finish to aid light reflection from the surface of the stone.
The gemstones used in Pandora jewellery are carefully measured, examined and sorted.
Grinding, usually with silicon carbide or diamond-impregnated wheels, is used to shape gemstones to a desired rough form, called a preform.
Colour variations of the aquamarine.