Aurorite

Aurorite is a dark-colored mineral with the chemical formula (Mn²⁺,Ag,Ca)Mn⁴⁺₃O₇·3H₂O. It is named for its type locality, the North Aurora mine in White Pine County, Nevada.^[1]

Aurorite
Aurorite crystals found in calcite
General
Category	Minerals
Formula	(Mn2+,Ag,Ca)Mn4+3O7·3H2O
IMA symbol	Aro
Identification
Color	Black, pale brown in transmitted light at the edges of very thin, platy grains
Luster	Metallic
Specific gravity	3.81