Mineral: Fluorite
Locality: West Green Mine, Saline Mines, Ozark-Mahoning group, Cave-in-Rock Sub-District, Hardin County, Illinois, USA
Dimensions: 18,5 x 13,5 x 12,0 cm

Description: Main crystal size:12.7 cm The lower portion of this specimen consists of corroded yellowish fluorite, the upper part of purple fluorite, the summit of which is complete and topped by small calcite crystals. The lower portion is a bit corroded. A possible explanation is that the lower part was formed by simultaneous crystallization of fluorite and Baryte and that competition between the two impeded the development of well defined crystals, while the upper part was formed from crystallization of fluorite alone and that occurred later (hence the difference in color). A later influx of fluid corroded and completely dissolved the Baryte on the lower part without attacking the fluorite, hence the ensemble's mushroom-like appearance. MIM number 1443 Photographer: FMI / James Elliott

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