| Tourmaline
is a gemstone noted for the large
and unsurpassed range of colors
in which it occurs. Tourmaline may
be heated to enhance it's color.
The treatment is permanent and accepted
in the trade, On our web site we
are usually quite specific about
which variety of tourmaline we are
referring to. Tourmaline is the
family name which includes the following
varieties; chrome (green), indicolite
(blue), rubelite (red), dravite
(brown), achroite (colorless), and
siberite (reddish-violet). Yellow
and green tourmalines are simply
called tourmaline with the color
as a prefix.
The
term "Tourmaline" has
been derived from "Thoramalli"
(Sinhala term). The yellowish brown
tourmalines are more abundant in
Sri Lanka. Tourmaline crystallizes
in the hexagonal system, as prismatic
Crystals with a "Rounded Triangular"
cross section and vertically striated.
They have vitreous lustre. Colors
include Red (Rubellite), Blue (Indicolite),
Yellow, Brown Green, Black colorless
or party colored. |
| Gemological
Information |
| Color
: |
Blue,
Bluish green, Green, Greenish blue,
Green-blue or Blue-green, Greenish
yellow, Orangy red, Red, Red-orange
or Orange-red, Red-purple or Purple-red,
slightly purplish red, slightly yellowish
green, strongly purplish red, strongly
yellowish green, very slightly bluish
green, Yellowish green, Yellow-green
or Green-yellow, Colorless, brown,
Pink |
| Refractive
Index: |
1.624(+.005,
-.005) - 1.644(+.006, -.006) |
| Chemical
Composition: |
(NaCa)(LI,MgFe,Al)9B3Si6(O,OH)31 |
| Hardness: |
7-7.5 |
| Density: |
3.06
(.05, +.15) |
| Crystal
Group: |
Hexagonal |
| Ocurrence: |
Brazil,
East Africa, Nigeria, Madagascar,
U.S.A. |
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