Vote for your favorite mineral in #MinCup26! - Sphalerite vs. Anorthite Both zinc ore Sphalerite and calcium plagioclase feldspar Anorthite have perfect cleavage that will split cleanly if you hit them with a hammer, but only one can claim a larger split of your votes!
It is worth noting that Kingsbury & Hartley (1956) suggest that "while there is no direct evidence, the historical and other data strongly suggest that the specimens [mottramite, and presumanbly other vanadium minerals] reputed to come from Mottram St. Andrew and Cheshire really come from Pim Hill. This view is also held by Sir Arthur Russell, who agrees with the substance of this note."
Grangers shaft, Mottram St Andrew, Cheshire, England, UK