Strontiomelane

Strontiomelane is an oxide mineral from the coronadite group in the hollandite supergroup.^[1] Specimens of the mineral appear very similar to other manganese oxides from the same group, such as the Ba-analogue hollandite. The type locality is the Praborna mine in Saint-Marcel, Italy.

Strontiomelane
General
Category	Oxide mineral > Hollandite supergroup
Formula	Sr(Mn4+6Mn3+2)O16
IMA symbol	Sml
Strunz classification	4.DK.05a
Crystal system	Monoclinic
Identification
Luster	Sub-Metallic
Specific gravity	4.66 g/cm3 (calculated)