Ankerite (Ca(Fe,Mg,Mn)(CO₃)₂) is the iron-magnesium-manganese variant of the dolomite group, forming a continuous solid-solution with dolomite. It is named after Austrian mineralogist Mathias Joseph Anker. Ankerite forms in iron-bearing carbonate sediments, ore-vein gangue assemblages, and as a hydrothermal alteration product. Common in Mississippi-Valley-Type (MVT) Pb-Zn deposits.
Key Facts
- Mohs hardness 3.5–4.
- Trigonal; isostructural with dolomite.
- Forms continuous series with dolomite (Mg-rich) and kutnohorite (Mn-rich).
- Tan to brown color, often with iridescent oxidation tarnish.
- Common gangue in MVT Pb-Zn-Ag-Au ore deposits.
Notable Localities
Eisenerz (Styria, Austria) is the type-area. Pribram (Czech Republic) and Cumberland (UK) yield collector specimens.
Found at these Localities
- Příbram (普日布拉姆银矿)
