pollucite
Pol"lu*cite, n. Etym: [See Pollux, and 4th Castor.] (Min.) Defn: A colorless transparent mineral, resembling quartz, occurring with castor or castorite on the island of Elba. It is a silicate of alumina and cæsia. Called also pollux.
Pol"lu*cite, n. Etym: [See Pollux, and 4th Castor.] (Min.) Defn: A colorless transparent mineral, resembling quartz, occurring with castor or castorite on the island of Elba. It is a silicate of alumina and cæsia. Called also pollux.