Mohs Scale Hardness: 7 -7.5

Chemical Composition: AD3G6(BO3)3[T6O18]Y3Z, where:

A = Ca, Na, K, or is vacant (large cations);

D = Al, Fe2+, Fe3+, Li1, Mg2+, Mn2+ (intermediate to small cations - in valence balancing combinations when the A site is vacant);

G = Al3+, Cr3+, Fe3+, V3+ (small cations);

T = Si (and sometimes minor Al3+, B3+);

Y = O and/or OH;

Z = F, O and/or OH.

[Note-1: Additional G and D site cations are reported substituting in minor amounts for the principal cations of these sites.]

[Note-2: The Y and Z sites are usually combined in the simplified formula for the Group as Z4.]  

Appearance:  Tourmaline is available in a wide variety of colors from black to bluish-black, dark brown, yellow, medium brown, blue to neon blue, lime to dark green, red and reddish purple, yellow, pink, and colorless.

Bi-colored and multicolored tourmalines may be green at one end and pink at the other, watermelon tourmalines are green on the outside and pink on the inside. Some stones are dichroic meaning they appear to change color when viewed from different angles.

Occurrence: Afghanistan , Africa, Australia , Brazil , Kenya , Madagascar , Mozambique , Nigeria , Pakistan , Siberia , Sri Lanka , Tanzania , U.S.A. , and Zimbabwe

Fact, Legend, Healing Properties: The name Tourmaline comes from the Sinhalese ( Sri Lanka ) word tura mali which translates as the stone of mixed colors.

Ancient legend says that tourmaline is found in all colors because it traveled along a rainbow and gathered all the rainbow's colors.

Tourmaline is believed to strengthen the body and spirit, especially the nervous system, blood, and lymphs. It is also thought to inspire creativity and was used extensively as a talisman by artists and writers.