 Chrysoberyl
ist a rhombic beryllium-silicate
with a hardness about 8,5.
Due to its greenish-golden colour it is very longing, especially chrysoberyl cat´s eyes, that show a light effect similar to those of cats´s eyes (chatoyancy). Chrysoberyl cat´s eyes are quite often only transparent, but alexandrite, 
that was also discovered as cat´s eyes, is really something special.
Alexandrite has the possibility to change its colour from green (in daylight)
to red (in artificial light).
This effect is caused by two different selective absorption spectra in different light-sources. Alexandrite und chrysoberyl occure in Zimbabwe, Madagascar, Burma und Sri Lanka. |
