Illinois fluorites are known for a lot of iconic aesthetics, and I think many of you fluorite collectors will agree that there is few that strike you like the blue with a purple phantom core.
These I feel are extra special when they have luster and good growth hillocks variation. The more it looks like a city or a wildly complex puzzle, the better (Although there is something to be said about a clean cube).
Fluorite - Denton Mine, Hardin County, Illinois, USA
11 x 9 x 7 cm.