5557 Calcite, Rhodochrosite, Quartz, Kara Mine, Hampshire, Tasmania

A mixture of Mn-rich calcite-Ca-rich rhodochrosite pseudomorphing kutnohorite, sitting on drusy quartz crystals. According to Ralph Bottrill, analyses showed  Mn40Ca60 and Mn75Ca25 from XRD.

This specimen is quite pale compared to others found on a field trip in 2005 so likely more towards calcite. The crystals also are zoned with a more transparent outer region. This was not really evident under the microscope, but shows clearly in the photo. The outer growth also appears to be the “stacked pancake” habit sometimes seen in calcite specimens from the mine.

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