SPARRY APHRITE. 121 Chemical Characters. It falls into pieces, with a crackling noise, when put into water. When touched with an acid, it effervesces with great violence, and is entirely dissolved in it. Geognostic and Geographic Situations. It occurs massive, imbedded, and in veins, in the first floetz limestone, in Thuringia, and Hessia. Observations. 1. The straight slaty variety passes into Slate-Spar, and into Scaly Aphrite. 2. Meinecke, and other old observers, described this mineral as a variety of Common Talc. It was first ac curately examined and described by Friesleben. Third Subspecies. Sparry Aphrite. Schaumspath, Friesleben. Schaumspath, Friesleben, Geognostiche Beitrage, b. ii. s. 234, External Characters. Its colours are snow, yellowish, and greyish white. It occurs seldom massive, generally disseminated; sometimes in flaky crusts, in veins, or imbedded in large crystals of selenite. It is shining, sometimes inclining to splendent, some times to glistening ; and the lustre is pearly, which in clines to vitreous in the splendent varieties. The
