Depending on their trace element content, sapphire, a variety of the mineral corundum, might be blue, yellow, green, orange, pink, purple or even show a six-rayed star if cut as a cabochon.
The name “sapphire” can also apply to any corundum that’s not ruby, another corundum variety.
Traditionally, sapphire symbolizes nobility, truth, sincerity, and faithfulness. It has decorated the robes of royalty and clergy members for centuries. Its extraordinary color is the standard against which other blue gems—from topaz to tanzanite—are measured. (source: GIA.edu)