Calcite with Hydrocarbons, Rosiclare Level, Cross-Cut Ore Body, Minerva #1 Mine, Ozark-Mahoning Company, Cave-in-Rock District, Southern Illinois, Mined c. 1990, Ron Roberts Collection UD-21, Miniature 4.0 x 4.5 x 6.5 cm, $25. Online September 14.
Mushroom-like formations of drusy calcite colored in shades of brown from hydrocarbon inclusions. These formations are highly characteristic of the NW Cross-cut Ore Body. In excellent condition. Ex: John and Clara Tolbert Collection, Cave-in-Rock.