The accompanying engraving represents an exceptionally fine group of crystals ofapatite, found in the Untersulzbachthal in Salzburg. The dimensions are those of the original, its colour is white with a delicate tint of mauve. This group is the finest of three of the most magnificent specimens yet found at this or any other locality, the largest one having been deposited in the national collection of minerals at South Kensington, while the third was unfortunately broken.