Third Supplement to Dana's Mineralogy. 



251 



Wown ; streak yellowish brown. Lustre semi-metallic. Thin splinters translucent. 

 Decrepitates strongly and loses water. B.B. in the platinum forceps infusible, but 

 becomes yellow : with borax, a glass which is brownish yellow while hot but green 

 and finally greenish yellow on cooling. In salt of phosphorus, a skeleton of silica. 



Breunnerite [p. 443]. — The Tautoclin of Breithaupt, occurs (N. Jahrb. f. Min. 

 etc., 1855, 842) in scalenohedrons, R 3 , or RA£R3, as pseudomorphs after calcite. 

 Occurs in the Himmelsfurst mine, near Freiberg ; also near Sachsenburg, Schnee- 

 berg, Przibram in Bohemia, &c. Ettling obtained for the tautoclin of Beschert- 

 Gliick, near Freiberg : 



0 45-75 Ca 27-48 Mg 15 85 Fe 9 25 Mn 129 = 97*62 



Calcite [p. 435, 503, and Suppl. i, n]. — A variety of curved columnar calcite 

 from Freiberg in Saxony, according to Kenngott (Pogg. xcvii, 311) has each column 

 made up of a series of tabular crystals — £R. oo R [of the form in fig. 574 C, p 435 

 of Min., only v^ry short] united in the line of the vertical axis. The diameter is 

 mostly 2 or 3 millimeters. — Other peculiar forms of grouping and modes of struc- 

 ture are described in the same paper. 



CARNALLITE, H. Hose. —Description by H. Rose (Pogg. xcviii, 161). Occurs 

 mixed with the stone salt of Stassfurt in coarse granular masses, having a shining 

 somewhat greasy lustre, and sometimes showing a plane surface after the action of 

 water over the surface, as if indicating structure or cleavage, but without any dis- 

 tinct traces of it in a fresh fracture. Dissolves easily in water. Composition ac- 

 cording to Mr. Oesten, assistant to Prof. Rose : 



MgCl KC1 NaCl CaCl 3Pe (mixed) H (loss) 



1. 3146 24-27 5 10 2 62 0 14 35 57 = 100 



2. 30 51 2427 4 55 3 01 0 14 36 26 = 100 



The water by direct determination was 37'27. Part of this water is united to the 

 chlorid of calcium, 2 54 p. c. in No. 1, and 2 9 1 in No. 2; so that the water of the 

 pure mineral is reduced to about 33 per cent. The composition then becomes K CI 

 + MgCl+12H. 



The name Carnallite is after Mr. von Carnall of the Prussian Mines. 



Chalcopyrite [p. 68 and Suppl. it]. — An account of the Cobre Lode of Santiago 

 de Cuba, by D. T. Ansted, is contained in the Quart. Jour. G-eol. Soc, xii, 144. 



Chalybite [p. 444]. — On the origin of the carbonate of iron in the Coal Measures, 

 W. B. Rogers, Proc. Bost. Soc. Nat. Hist., 1855, 283, and Am. J. Sci., xxi, 339. 



CHEROKINE, O. U.Shepard.— K species as yet imperfectly described by the 

 author. Crystallizes like pyromorphite but has the color of carbonate of lead. 

 Specific gravity, 4 8. Stated to contain phosphate of alumina and zinc. [The form 

 given, near pyromorphite, would suggest the improbability that the mineral is a 

 phosphate of a sesquoxyd with zinc, unless a pseudomorph. — j. d. d.] 



CHLOROPH A NERITE, G. Jenzsch.— From the amygdaloid in the vicinity of 

 Weissig. It had been referred to chlorophaate, and ferruginous chlorite (Delessite), 

 but differs in its very large percentage of silica. G. Jenzsch obtainel (N. Jahrb. f. 

 Min. etc., 1855, 798,) in a partial analysis, Silica 59*4, protoxyd of iron 12 3, water 

 5-7, the alumina, magnesia, lime, potash, soda, undetermined. — Color blackish-green; 

 streak dirty apple green ; soft ; G. = 2 684. BB. yields easily a magnetic glass. 

 In muriatic acid dissolves readily, the silica separating. According to Dr. Oschatz, 

 the particles of a crystalline group magnified, showed slight double refraction. It 

 approaches nearest a green earth from Iceland analyzed by von Waltershausen, 

 which gave. Si 60-085, £15-280, Ca 0'095, Mg 4 954, Fe 15-723, K 5 036, Na 2-5 14, 

 H 4-444 = 98-131 (Vulk. Gest., p. 301). 



Chrysolite [p. 184. and Suppl. i, nj. — A mineral looking like some kinds of 

 amorphous garnet, occurs at Plunders in the Tyrol, in a talcose serpentine rock 

 traversed by veins of calcite. A specimen in the collection of M. Adam of Paris 



