This piece is a pretty dolomite but it is also much more than that, to our eyes. This crystal is a major example of the species, with glistening bright surface luster and total transparency. It is one of the prettiest examples of the species I have seen from this or any other location (including the famous Spanish locale for rhombs), and the geometry of the sharp twinning is striking, and unique to this particular locale. Again not only is the gemminess startling, but it is more clean and clear than the famous gem dolomites from Spain, which form penetration twinned rhombohedra quite different in form from what you see here. This crystal is complete-all around save only some minor contacting in the lower-left and the bottom. It is complete on the backside, as well. This is from a European collection.