104 CYPROXICA. 



Analysis by Richardson : 



Silica 38"80 



Alumina .... 20-40 

 Protoxide of iron . . . 8 35 

 Lime ..... 320 



99-55 

 Locality. The neighbourhood of Telle- 

 marken in Norway. 

 Brit. Mus., Case 35. 

 Cypronica, Necker. See Chalcophyl- 



UTE. 



D. 



Damourite, Delesse. A variety of Mar- 

 ^arodite; perhaps a hydrous Muscovite. 

 Colour yellow or yellowish-white with a 

 pearly lustre and a scaly texture. 



Comp. (JgR3xfgif)"Si + H. 



Locality. Pontivy in Brittany, associated 

 with Kyanite. 



Name. After Damour, the French chemist. 



Brit. Mus., Case 26. 



Danaite. a cubaltic variety of Mis- 

 pickel. 



Comp. (Fe, Co) (As, S)2. 



Analysis hy Hayes : 



Arsenic .... 41'44 

 Sulphur .... 17-84 



Iron 32-94 



Cobalt ..... 6-45 



98-67 

 Name. After Professor Dana, of Yale 



College, U.S. 



Danburite, Shepard. 



Anorthic : occurs in imbedded crystals, also 



disseminated massive, without regular form. 



Colour whitish or pale yellow, with a weak 



vitreous lustre. Translucent. Very brittle. 



H.7. S.G. 2-9.5. 



Comp. Ca3 8i + 3 B Si = silica 48-9, boracic 

 acid 28-4, lime 22-7 = 100-0. 

 Analysis by Smith Sf Brush : 



Silica 48-10 



Alumina and peroxide of 



iron . . . . 0-30 



Peroxide of manganese . 0-56 

 Lime ..... 22-45 



Magnesia 



. 0-40 



Boracic acid 



. 27-73 



Undetermined 



. 0-50 



100-00 



DARWINITE. 



BB fuses rather easily. In the dark co- 

 lours the flame green, especially after the 

 assay has been moistened and heated with 

 sulphuric acid. 



Locality. In dolomite with Oligoclase at 

 Dan bury, Connecticut, U.S. 



Danburite may be distinguished from 

 Chondrodite, which it resembles in colour, 

 lustre, and brittleness, by being distinctly 

 (though often irregularly) cleavable. 



Dannemorite, Kennyott, Erdmann, a 

 variety of Hornblende, consisting of strongly 

 consolidated tibres, of a greenish, greyish, or 

 yellowish-brown colour. S.G. 3-516. 



Comp. R4'^i5. 



Locality. The iron mines of Dannemora, 

 in Sweden. 

 Daocrit. See Rttbelute. 

 Dapechb. See Elastic Bitumen. 

 Dark Red Silver Ore. See Pyrargy- 



RITE. 



Darwinite, David Forbes. A new mineral, 

 supposed, when first discovered, to be native 

 silver. Massive, without traces of cleavage. 

 Colour of freshly-fractured surface dark sil- 

 ver-grey, tarnishing on exposure to dirty 

 bronze-yellow. Opaque. Lustre metallic. 

 Streak metallic, dark silver-grey. Rather 

 brittle and easily broken ; receives an inden- 

 tation from the hammer before A'ielding. 

 Fracture even. H. 3-5. S.G. 8-57 "^to 8-69. 



Comp. Cui8 As = copper 88-37, arsenic 

 11-63 = 100. 



Analysis by David Forbes : 



Copper 88-07 



Silver 0-24 



Arsenic . . . .11-09 



100-00 

 Heated in a close tube does not alter, or at 

 most a f;iint trace of arsenious acid sublimes 

 on to the side of the tube. In an open tube 

 a distinct white sublimate of arsenious acid 

 is obtained. 



BB on charcoal in reducing flame fuses 

 readily to a silver-white globule, which in 

 the act of cooling evolves arsenical fumes, 

 and becomes slightly red on the surface; in 

 the oxidizing flame on charcoal evolves 

 abundant arsenical fumes, rotates, and ulti- 

 mately leaves a globule of metallic copper, 

 malleable, but still retaining some arsenic: 

 on cupelling this button of copper with lead, 

 a minute globule of silver is obtained : with 

 fluxes gives the reactions of copper only. 



Locality. Potrero Grande, S.E. of the 

 town of Copiapo, in Northern Chili, where 

 it is said to occur in small veins or strings, 

 seldom attaining a breadth of more than 



