A very IMPORTANT LOCALITY SPECIMEN!!! Open for only ten years in the mid-1900s, the Deardorff Mine is not one of the household names when it comes to Illinois fluorite. However, it had a unique association of fluorite and quartz which remains one of the most sought-after Illinois classics to this day. For whatever reasons, quartz is rare in the other nearby mines, particularly in association with good fluorite. This association, is both dramatic and classic for the mine - if in somewhat larger size than we usually see. The fluorite cubes, to 3.75 cm across, exhibit good luster and near-transparency along with a fine pastel- blue color. There is almost no damage except the most trivial nicks...it is nearly pristine! When viewed from the side there is a hint of color zoning with purple overtones. The lavender fluorescence adds to the beauty of this specimen. But it is the merger of the history and rare association here WITH quality of the fluorite itsel fthat makes it so valuable. I have purposefully chosen to leave the piece uncleaned with modern technology which could remove the iron pocket-staining and make the piece look too modern and sparkly. I llike the old look, in this case. It just has the feel of something non-Chinese, if that makes sense?!