Purpurite is an alteration product of an equally rare mineral called lithiophyllite , LiMnPO 4 . With the change in charge in the manganese ion, the lithium ion is then lost. Often some of the original lithiophyllite is still present in most purpurite specimens. The purple color or purpurite is truly unique in the mineral rainbow. Luster is vitreous to sub-metallic.
Crystals are translucent to opaque.
Cleavage is good in one and poor in another direction. Fracture is uneven. Hardness is 4 - 4.5. Streak is deep red to purple. Brown coatings can be removed by weak acid baths that can also bring out more purple color.