General Information:
Chemical Formula:
(Mn,Ag,Ca)Mn++++3O7·3(H2O)
Composition:
(Molecular Weight = 398.70 gm)
Calcium 2.01 % Ca
Manganese 48.23 % Mn
Silver 8.12 % Ag
Hydrogen 1.52 % H
Oxygen 40.13 % O
Empirical Formula:
Mn2+0.5Ag0.3Ca0.2Mn3+3O7·3(H2O)
IMA Status:
Approved IMA 1967
Locality:
Aurora mine, Treasure Hill, Hamilton, Nevada, USA.
Name Origin:
Named for the locality.
Physical Properties:
Color:
grayish black or black.
Density:
3.8 - 4.1, Average = 3.95
Diaphaniety:
Opaque
Habits:
Irregular Grains - Occurs as splotchy, anhedral crystals forming inclusions in other minerals or rocks., Platy - Sheet forms (e.g. micas)., Scaly - Morphology like fish scales.
Hardness:
2-3 - Gypsum-Calcite
Luster:
Metallic
Streak:
brown
More details...