for base has two rectangles. It is found enclosed in a matrix of white felspar, grey quartz, and granite.
rare, it is not of much value, although it enjoys a special singularity
; when cut and polished it presents internal milky-blue reflections,
which seem to follow the different inclinations given to the stone ;
and this peculiarity has originated the name of cymo-phane given to
this gem by Hauy.
to the present time it has only been procured from Brazil, Ceylon,
Connecticut, in the United States, and Nortschink, in Siberia.
The cymophane of Brazil is generally found in fragments, of the specific weight of 3*7337. When analysed, it gives