This is one of the best, most pristine examples of the rare cadmian smithsonite with large crystals and bright color that was found in one pocket in the early 1970's: that is still regarded as producing the best of its type. The cadmian deposits are layered into the outer layers of the large rhombohedral crystals(to about 1 inch in size!), leaving white and yellow zones when looked at in cross-section. However, this piece presents a solid mound of intensely-colored yellow to the viewer, and the color is not only more evenly distributed than on most such specimens but more intense as well. It is pristine, save for the bottom periphery. A comment from Dr. Bruce Cairncross, author of the book The Manganese Adventure: I can't be too specific re the Cd-smithsonites, but they were collected during the early 1970's, certainly pre-1975 when I started seriously collecting. Des Sacco confirms this period and he says there were'nt more than several found in a small pocket. 8 x 6 x 4 cm