Citrine

Citrine, also called citrine quartz or citrine topaz, is an amber-colored gemstone. It is a form of quartz with ferric iron impurities, and is rarely found naturally. Most commercial citrine is in fact artificially heated amethyst or smoky quartz. Brazil is the leading producer of naturally mined citrine, with much of its production coming from the state of Rio Grande do Sul.
In ancient times, citrine was carried as a protection against snake venom and evil thoughts.
Citrine is one of two traditional birthstones for the month of November
References
- International Colored Gemstone Association page on citrine

Source from Wikipedia