Calcite and Dolomite from Langban, Sweden
Contributed by: Michael Crawford
Date: Aug 17th, 2025
Locality: The Lake dump, Långban Mine, Långban Ore District, Filipstad, Värmland County, Sweden (See on Mindat)
Size: 8 x 10.5 cm
Description:
A banded Calcite (CaCO3) and Dolomite (CaMg(CO3)2) specimen from the Lake Dump, Langban Mine, Varmland County, Sweden. The calcite fluoresces orange red under all wavelengths of UV light. The dolomite is dark red under shortwave UV light. It is considerably dimmer under longwave and midwave UV light. Neither mineral fluoresces in the ultraviolet region like many other red fluorescent calcites.
The shortwave emission spectra show that the peak fluorescence of the calcite and dolomite are different. The calcite maximum is at 626 nm and the dolomite maximum is at 643 nm. The fluorescence is activated by manganese in both minerals.
Summary of luminescence responses:
Calcite (Mindat) (RRUFF)
- Fluorescence under Longwave (365nm LED) UV light: Red
- Fluorescence under Midwave (305nm LED) UV light: Red
- Fluorescence under Shortwave (255nm LED) UV light: Red
- Fluorescence under Shortwave (255nm LED) UV light: Red