Template:POTD/2010-12-22

Picture of the day
Amethyst crystal
Amethyst is a violet variety of quartz often used in jewelry. The color is a result of irradiation which causes the iron ions present as impurities in quartz to rearrange themselves in the crystal lattice. On exposure to heat, the irradiation effects can be partially cancelled and amethyst generally becomes yellow or even green.Photo: Noodle snacks