铯榴石; 铯榴石
Pollucite \Pol"lu*cite\, n. [See {Pollux}, and 4th {Castor}.]
(Min.)
A colorless transparent mineral, resembling quartz, occurring
with castor or castorite on the island of Elba. It is a
silicate of alumina and c[ae]sia. Called also {pollux}.
pollucite
n : a rare mineral that is an important source of cesium