Hollandite

Hollandite (chemical formula: Ba(Mn4+6Mn3+2)O16) is an oxide mineral. It is the barium-manganese (III) endmember of the coronadite group. 
A mineral, with the chemical composition BaMn4+6Fe3+2O16, that was first found in the Kajlidongri mine in the Jhabua district of Madhya Pradesh, India, had the name "hollandite" until it was reclassified as "ferrihollandite" by the International Mineralogical Association in 2012. Ferrihollandite is the barium-iron (III) endmember of the coronadite group.
Rare quartz inclusion