Boleite is a complex halide mineral. Boleite is a rare secondary mineral from copper deposits, typical of arid climates in a chlorinated environment (closed basins, evaporite lagoons, and marine littoral). The external property of a boleite crystal structure indicates its cubic structure.
Boleite is classified under the isometric crystal class. Boleite has a perfect cleavage in the  direction, and has a very dark glossy blue color with a light greenish-blue color streak.
|Complete cluster of cumengeite crystals epitaxial on a boleite cube from Santa Rosalia, Boleo District, Baja California Sur, Mexico|
Photo: Bucket of Holes Minerals/E-rocks
Twinning is best shown in this mineral by notches along the interpenetrated angles, which results in a crystal habit of pseudocubic penetration twinning along three different angles perpendicular to one another.
Colour: Deep prussian blue to indigo; bluish green in transmitted light
Lustre: Vitreous, Pearly
Hardness: 3 - 3½
Crystal System: Isometric
Name: For the occurrence at Boleo, Mexico.
Occurrence: A secondary mineral formed through reaction of chloride with primary sulfides in the oxidized zone of Pb–Cu deposits; in smelter slag immersed in and leached by sea water.
|Boleite Crystal Information, |
From: Curuglu Mine, Arroyo del Boleo, Mulegé Municipality, Baja California Sur, Mexico
Photo: Jean-Marc Johannet
There are numerous minerals related to boleite, such as pseudoboleite, cumengite, and diaboleite, and these all have the same complex crystal structure.
Boleite was first collected as a very minor ore of silver, copper and lead at Boleo, Mexico. Minerals associated with boleite include pseudoboleite, cumengeite, atacamite, anglesite, cerussite, phosgenite and gypsum at the type locality in Boleo, Mexico. In the Mammoth-St. Anthony mine of Arizona associated minerals include pseudoboleite, anglesite, cerussite, atacamite, paratacamite, leadhillite, paralaurionite, caledonite, phosgenite, matlockite and bideauxite.