Philipsburgite

Philipsburgite – Cu5Zn(AsO4)(PO4)(OH)6·H2O
Class: Arsenates
Crystal System: Monoclinic
Hardness: 3-4
Fluorite
Talc (1)Diamond (10)
Softer than glass. A steel knife scratches it.
Origin: Black Pine Mine Granite Co., Montana – Usa
Did you know?

Philipsburgite has a quiet identity problem. In 2021 it was redefined and split off a near-twin, goldhillite, so many specimens long labeled philipsburgite, especially those from outside the original Montana mine, have since turned out to be the other mineral.