Sampleite
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Sampleite has a general formula of NaCaCu₅(PO₄)₄Cl·5. It was first described in 1942 for an occurrence in Chuquicamata, Chile and was named after Mat Sample, a mine superintendent for the Chile Exploration Company.
Sampleite is monoclinic. It... Wikipedia
Cleavage: Perfect on; good on, and
Crystal class: Prismatic (2/m); (same H-M symbol)
Crystal habit: Aggregates, lath, rosette
Crystal system: Monoclinic