Tourmaline
The name tourmaline comes from the Sinhalese word "turmali" for "mixed colors." This is another stone that comes in virtually all colors, and some even combine colors in the same stone. Red tourmaline is sometimes known as rubellite, blue as indicolite, and green as verdalite. A beautiful and rare type of tourmaline (known as Paraiba tourmaline) is highly sought-after and is one of the most expensive varieties of gemstones. Tourmaline is the traditional birthstone for October. They are a bit more delicate than other gemstones, so care must be taken when setting and cleaning.