Complex sentence: It was first described by August Breithaupt in 1846 for occurrences on the island of Elba, Italy, it is named for Pollux, the twin of Castor on the grounds that it is often found associated with petalite (previously known as "castorite").
Split into simpler sentences: It was first described by August Breithaupt in 1846 for occurrences on the island of Elba, Italy. It is named for Pollux, the twin of Castor on the grounds that it is often found associated with petalite (previously known as "castorite").