Tourmaline Gemstone Properties Tourmaline gemstones, the
birthstone for October come in a rainbow of color , tones and
hues. In fact it is sometimes referred to as the “gemstone of
the rainbow”. There are actually ten separate mineral species in
the tourmaline gemstone group, of which only three are suitable
as gemstones. The elbaite species is the one that is most often
used for creating beautiful jewelry. The color in tourmaline is
a result of substitutions of various transition elements or
metals in the crystal structure. Rarely can one find a
tourmaline crystal with a single color, most tourmaline crystals
are found with numerous colors. Tourmaline is a very dichroic
gemstone, meaning that colors look more or less intense
depending on the viewing angle. This presents challenges to the
gemstone cutter when orienting the gemstone for best color.
Tourmaline is a fairly hard (7-7.5 on Mohs scale) and mostly
durable gemstone. Some tourmalines can crack or become unstable
due when faceted or heat treated. Color