Spodumene frequently occurs as long, large, unevenly terminated, flat sided crystals, often with longitudinal striations. Some of these crystals are among the largest in the mineral world. Crystals a few meters in length, weighing over a ton, have even been found. Most often, crystals are a faintly green, nontransparent whitish gray- hence the name which refers to ash. Violet pink, bright green, yellow green, or yellow specimens are much less common and transparent crystals of these are used as gems. Transparent crystals have vitreous
luster and marked pleochroism
. The semi-opaque crystals look almost pearly and have easy prismatic cleavage
. Kunzite is a beautiful brilliant stone, which occurs in lilac, pink and violet shades. Kunzite is distinctly pleochroic- when the gem is turned; different shades of pink and violet are displayed. The pink color may fade with time, or with exposure to light and heat, but some material is irradiated to intensify it. Because of its sensitivity to light, the stone has been become known as an evening stone. Kunzite is a hard stone, but is nonetheless brittle and difficult to cut. Hiddenite is a more rare variety of spodumene that comes in light green or yellow green varieties. Emerald green varieties are sometimes found, but are very scarce. As with kunzite
, it is hard but brittle, so care must be taken when wearing this stone. It is also strongly pleochroic, like kunzite, showing green, bluish green, and yellowish green when viewed from different directions. Its color will also fade with exposure to heat. Spodumene has a hardness of 7, and a vitreous luster. It occurs in a wide range of colors, all pale, but very clear and brilliant.