No gemstone has such richness in color and variation Known in antiquity in the Mediterranean area. The Dutch imported it in 1703 from Sri Lanka into Europe. The new stone was given a Sinhalese name Turamali.

• Color : Colorless, pink, red, yellow, brown, green, blue, violet, black, multi-colored
• Color of streak : white
• Mohs' hardness : 7-7 1/2
• Specific gravity : 3.02-3.26
• Cleavage : None
• Fracture : Uneven, small Conchoidal, brittle
• Crystal system : Hexagonal (trigonal); usually long crystals with triangular cross section with rounded sides, definite striation parallel to main axis, often several prisms grown together
• Chemical composition : (NaLiCa) (Fe11 Mg Mn Al)3Al6((OH)4 (BO3)3Si6O18) aluminum borate silicate, complicated and changeable composition
• Transparency : Transparent, opaque
• Refractive index : 1.616-1.652
• Double refraction : -0.014 to -0.044
• Dispersion : 0.017
• Pieochroism : red :dark red-light red
  Yellow : definite; dark brown-light yellow
  Green : Strong; dark green-light green
  Blue : Strong; dark blue-light blue
• Absorption spectrum : Red : 5550, 5370, 5250-4610, 4560, 4510, 4280
  Green : 4970, 4610, 4150
• Fluorescence : Colorless : Weak; green-blue
  Pale yellow : Weak; green-blue
  Red : Weak; red-violet
  Pink, brown, green, blue : none