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!
Kingsbury reference. Cooper & Stanley (1990): "'From the 'Dumpy Stone' level as 'small residual patches with considerable amounts of... beudantite, together with red-brown scorodite, beaverite, and "limonitic" matter' (Kingsbury & Hartley, 1960: 429).
Also from the Nether Row Farm level with beudantite, scorodite, and arseniosiderite; specimens may still be collected from this locality, as minute crystals or thin crusts on vein quartz."
Nether Row Brow, Caldbeck, Allerdale, Cumbria, England, UK