Calcite on Sphalerite, Rosiclare Level Cross-Cut Orebody, Minerva #1 Mine, Ozark-Mahoning Company, Cave-in-Rock District, Southern Illinois, Mined March 1992, Kalaskie Collection #731, Miniature 4.0 x 6.0 x 7.0 cm, $25. Online 11/6.
Light brown calcite on deep brown sphalerite. Note the contrasting luster on the sphalerite caused by dissolution of barite: higher luster area was not enclosed by barite. Advance mining march 1992. In excellent condition. Betty Kalaskie Collection #731.