Bergmannite

This mineral has been considered by some as a variety of Scapolite, tab. 68: it is so compact that the structure of its fibres cannot be discovered; its fusibility into a white enamel and some of its other characters agree with those of Scapolite, but several of our best mineralogists still class them separate. The specimen figured is in the British Museum; it is from Friedrichswärn in Norway; the Feldspar accompanying it is chatoyant.

Another specimen, lent me for examination by Mr. Heüland, who received it from Norway under the name Spreüstein, shows some minute fasciculi of acicular crystals, which under the magnifying glass appear to be hexahedral prisms, two of the angles of which are nearly rectangular, and two of their terminal edges more or less deeply replaced by a single face each placed at a very obtuse angle upon the side of the prism.

A specimen purchased at the sale of Dr. Lettsom’s minerals is marked “from Homerberg, in the parish of Kylling, near Stavern, Norway,” has also some minute crystals of a similar form upon it.