Choose a lens
These inclusions are called negative crystals. They are hollow spaces and their shape is controlled by the crystal structure of amethyst. Note the inclusion in the center. It has the shape of an amethyst crystal. - Photo by Dr. E. J. Gübelin/GIA
The inclusion in this amethyst shows a pattern called soapscum or zebra-stripe. Which term do you like better?
The inclusions in this light-colored amethyst contain liquid and gas. - Photo by Dr. E. J. Gübelin/GIA