GOSHENITE, a gemstone variety of beryl

GOSHENITE, the colorless variety of beryl

VARIETY INFORMATION:

VARIETY OF: Beryl , Be3Al2Si6O18 .
USES: Gemstone and as a source of beryllium.
COLOR: Colorless.
INDEX OF REFRACTION: 1.57 - 1.60
BIREFRINGENCE: 0.004 - 0.008
HARDNESS: 7.5 - 8
CLEAVAGE: one direction, poor.
CRYSTAL SYSTEM: hexagonal
Pleochroic:not discernible.
SPECIMENS

Goshenite is a variety name applied to the colorless beryl, the "mother of gemstones".

Other gemstone color varieties that belong to beryl include emerald, green beryls; heliodor, yellow beryls; morganite, pink beryls and aquamarine, blue beryls. Other colors of beryl are simply referred to by their color, such as in golden beryl and red beryl. Since all these color varieties are caused by impurities and pure beryl is colorless, it might be tempting to assume that goshenite is the purest variety of beryl. However, there are several elements that can act as inhibitors to color in beryl and so this assumption may not always be true. The name goshenite has been said to be on its way to extinction and yet it is still commonly used in the gemstone markets. Goshenite is found to some extent in almost all beryl localities.