Birthstone: November

Hardness: 7

Citrine is the most affordable of all the earth-toned gemstones, thanks to its durability and availability.

Citrine, a form of quartz, derives its name from the French word for lemon, "citron." It is available in a range of golden hues from lemon to straw to sun yellow to gold, as well as oranges, browns, and deep madeira red.

In ancient times, citrine was carried as a protection against snake venom and evil thoughts. It was also thought to give calmness and mental balance to its wearer.

Most citrine is mined in Brazil. Supplies are most plentiful in the Brazilian state of Rio Grande do Sul, particularly from the Serra mine.

These stones generally start life as either smoky quartz or amethyst geodes. Heat treatments first turn them clear and then give them a permanent color ranging from yellow to brownish red.

Occasionally, Mother Nature combines the colors of amethyst and citrine into a single gemstone called ametrine.