Citrine, November birthstone
A clear point of citrine, although it is most likely not a natural citrine but heat-treated amethyst. Amethyst and citrine are actually both forms of quartz. Citrine does not occur very often naturally, as it requires the right combination of heat and pressure to change the oxidation state of the iron impurities in amethyst to that of citrine. It is readily done commercially though. This piece is mounted in a brass ring base. Citrine is a November birthstone.
Approximately 1/2 inch (1.3 cm) in diameter and 3/4 inch (1.9 cm) tall.