Choose a lens
The needle-like inclusions in this sapphire prove that its color is natural and not the result of heating. Heating would have caused the inclusions to dissolve or break up. - Photo by Clayton Welch/GIA
There are some interesting cracks in this sapphire from Sri Lanka. Tiny crystals and other materials grew in the cracks while the gem was still in the earth. - Photo by Dr. E. J. Gübelin/GIA
This sapphire’s disk-shaped inclusion is called a discoid [dis-koyd] fracture.