A MAJOR rarity in the world of Illinois fluorite, featuring not only very large crystal size (there is a crystal here that measures over 6 cm along the edge!), but also, wonderful zoning, with dark purple phantoms glowing in the center of the lighter-colored exteriors. the Minerva #1 mine was a separate mine owned by the Minerva Oil Co. about 4 miles SE of the Spivey. The Spivey is also referred to as the Green mine in some ISGS literature and is (mis) spelled "Greene mine" on one ISGS Geologic map.