A new mineral, isomorphous with trechmannite, from the Binn valley, Switzerland

Extract

In August 1904 I discovered in the Lengeubach quarry a specimen on which were three small, round-shaped crystals, about the size of small shot, grown upon a prismatic crystal of sartorite. I measured them, and owing to their small size experienced some difficulty in determining the position of some of the faces with the goniometer at my disposal, which was of the ordinary single-circle pattern.