At 2.7 cm in length, this individual, sharp, monoclinic crystal of Whewellite is worldclass for both its size and perfect form. Found in 1983, it is from Feldstrecke 1300, 435 Meter Level (Sohle), Upper Floor, Level 3, Shaft 396 at Paitzdorf mine near Ronneburg in Thuringia, Germany. Not only is this an exceptional crystal for this rare calcium oxalate species, but it is on matrix too - a small plate coated with finely crystallized Calcite and Pyrite. Allied to its superb crystallographic shape, the Whewellite is colour-zoned from light to dark grey, caused by inclusions of metallic Smythite, an iron nickel sulphide. There are a few very tiny nicks along the edges of the Whewellite but there always is with this soft mineral, and this compared to others, is truly exceptional.
