| 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. |
| Shows
multiple color zones throughout
the crystal. Highly prized when
the colors are well divided and
vivid. Often badly included and
subject to fracture along the color
transition line |
|
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|
