Sapphire (Greek - blue) used to be applied to a variety of stones. In antiquity and as late as the Middle Ages, Sapphire was used in the same sense as lapis lazuli is used today. Around 1800 sapphire and ruby were of the corundum variety. At first the blue ones were considered sapphire, and the other color corundum (with the exception of red) special misleading names, such as "Oriental peridot" for the green variety and "Oriental topaz" for the yellow type. Today corundums of all colors except red are called sapphires. Red varieties are called rubies. Sapphires are referred to by description i.e. yellow sapphire, green sapphire. Sapphires without the qualification are called "blue corundum". Orange pink sapphire is called padparadschah (sanahlese for "Lotus Flower").

• Color : Blue in various hues, colorless, pink, orange, yellow, green, purple, black
• Color of Streak : White
• Moh's harness : 9
• Specific gravity : 3.99-4.00
• Cleavage : None
• Fracture : Small Conchoidal, uneven, splintery
• Crystal System : Hexagonal (trigonal); dipyramidal, darel-shaped, tabloid-shaped
• Chemical composition : Al203 Aluminum oxide
• Transparency : Transparent; opaque
• Refractive index : 1.766-1.774
• Double refraction : -0.008
• Dispersion 0.018
• Pleochroism : Blue : definite; dark blue, green-blue
  Yellow : weak; yellow, light yellow
  Green : weak; green-yellow, yellow Purple : Definite; purple light red
• Absorption spectrtrum : Blue, from Sri Lanka: 4710, 4600, 4550, 4500, 3790
  Yellow: 4710, 4600, 4500
  Green: 4710, 4600-4500
  
• Flourescence : Blues: (purple) none
  Yellows from Sri Lanka: weak; orange Colorless : orange-yellow or purple