Not sure if birefringence is appropriate description, or if it is just my
definition of "birefringment". the crystals that we observed were opague
and stained red, not what I considered "normal" crystal appearance. anyone
have any help with this? I know the dictionary definition and I dont want
to get into index of refraction etc. (or I could ask on the confocal
server)  I just want clarification of the term when is comes to
observing crystals under the scope and a description of what is observed.
i.e. transparent etc.
thanks
anita