Cryolite is a very rare halide and this very rare old-time specimen is from St. Peters Dome, El Paso County, Colorado. Moderately lustrous and translucent, light gray, columnar-jointed, massive cryolite comprises this entire specimen. Iron oxides give the piece character. Accompanied by an expertly handwritten, faded label from an older collection. The collection this came out of was a museum stash dating to prior to World War I.