Cumengeite, also known as cumengite, is a secondary mineral that was named after mining engineer Bernard Louis Philippe Édouard Cumenge, who found the first specimens.
During the growth, the new crystalline layers are formed with at least one well-defined orientation.
Til these days, that mine is the only one that had produced well-formed cumengeite crystals of any significance.
Cumenge, the one who found the mineral also collected it from its type locality, Boleo.
[4] It appears in lead or copper deposits' secondary, oxidized zone.