15 carat natural tanzanite crystal, untreated, multiple faces on the
termination. The colour shown here is the colour under halogen lights and
natural light (sun).
A large, beautiful 88.7 carat, gemmy, naturally purple crystal. This specimen
has not been heat treated. Some of these crystals are naturally baked
through the geologic ages. This crystal in particular shows excellent colour
near the top and grades into a yellow-green at the base. The crystal is
terminated and shows thin to thick platy forms like so many show and is
vertically striated.
Natural, untreated 52.8 carat crystal showing excellent crystal forms,
vertically striated, very lustrous lilac or purple coloration to light
yellowish green depending on the angle - tanzanite displays remarkable
pleochroism. There is a little
graphite
matrix still attached.
A 25 carat, purple to lilac coloured termination to yellowish green base,
natural crystal, untreated, very gemmy and well formed crystal.
Naturally deep purple, untreated 64 carat well-formed crystal showing an
excellent termination, bladed or deeply striated. The crystal is a dark
green at the base.
A 38 carat, terminated and well formed crystal showing good purple colour,
very gemmy, untreated natural crystal.
Origin: Merelani HIlls, Umba Valley, Lelatema Mts., Arusha, Tanzania
Sample size: 18 x 14 x 8 mm (top), 3.5 x 2 x 1.3 cm (2nd row), 3.5 x 1.5 x
1.5 cm (3rd row), 3 x 1 x 1 cm (4th row), 3 x 1.5 x 1.8 cm (5th row), 3.6 x
1.9 x 1 cm (bottom)
