Herderite

Herderite is a mineral belonging to the apatite, phosphate group, with formula CaBe(PO4)(F,OH). It forms monoclinic crystals, often twinned and variable in colour from colourless through yellow, green or purple.

It is found in many parts of the world, often in pegmatites and associated with other apatite minerals.

It is named after Sigmund August Wolfgang von Herder, a mining official from Saxony.

Herderite