Located on the banks of the Mississippi River in Buffalo, Scott Co., Iowa, the Linwood Mine is one of the largest underground limestone mines currently in operation in the United States. The Linwood Mine is known to produce beautiful, museum quality calcite and barite crystals. Of interest to fluorescent mineral collectors, the Linwood Mine also produces interesting fluorescent specimens.
This is a classic specimen from the Linwood Mine, consisting of colorless, transparent, modified rhombohedral calcite crystals, some with minor marcasite inclusions, on a minimal grey limestone matrix. This is a beautiful display specimen under normal light, but also shows a lovely, soft, purple/magenta fluorescent response under mid wave UV. The size of this specimen is 15.1 x 14.6 x 7.2 cm, and it weighs 1249 grams.
As shown above, a moderately bright purple/magenta fluorescent response is seen under mid wave UV (302 nm). As is the case with much of the fluorescent calcite from the Linwood Mine, this specimen shows its brightest response under mid wave UV.
When viewed under visible light, as shown above, this specimen makes a beautiful display piece.