paratacamite

Century Dictionary and Cyclopedia

1. n. An oxychlorid of copper having the same percentage composition as atacamite, but losing its water at a higher temperature. It occurs in pseudorhombohedral crystals, and is found at Sierra Gorda, Chile.

Wiktionary

1. n. mineralogy A rhombohedral form of basic copper chloride that is dimorphous with tacamite