t 



APPENDIX. 3 



Barettite. A name given by Bombicci to a mineral from Traversella in the province of 

 Ivrea. having the following characters : — Occurs in nodular, radiated, and fibrous masses. 

 H.=2'5. Gr.=2'5. Color apple-green. Streak white. Feelsoapy. Analysis gave Si 30 '00, 

 Ca 33-70. Mg 10-00, Fe 7*20, Si 1-60, C 91, H 1:2, with a small amount of sulphuric acid, 

 and probably also containing phosphoric acid and alkalies. (Atti della Soc. Ital. di Sc. Nat. 

 si., in Jahrb. Min., 1868, 750. 



66 A. Betkichite. K Th. Liebe, Jahrb. Min., 1871, 840. 



Hexagonal ? Occurring in screw-shaped groups, radiated in structure, the constituent 

 prisms of which are about 70 mm. long and 8 mm. wide. One terminal plane makes an angle of 

 81 c with the vertical axis ; a second, rarer, inclines to the first at an angle of 144°, the angle of 

 the rhombohedron of millerite. Cleavage rather perfect parallel to the first of these planes, 

 and no other cleavage direction observed, so that the rhombohedral character of the crystals 

 is not certain. 



H=3 — 3 - o. G-.=4 - 7. Lustre metallic. Color lead-gray. Composition 3 Ni S+ 2 Ni S 2 =S 

 43 '21, Ni o6"79=100. An analysis by Liebe gave : 



S Fe Ni 



42-86 2-79 54" 23 =99 -88 



B. B. in the closed tube decrepitates and gives a sublimate of sulphur, on charcoal fuses 

 to a brass-yellow magnetic globule. Soluble in nitro-muriatic acid, yielding an emerald 

 green solution. 



From Lammrichs Kaul Mine in Westerwald, where it is associated with millerite. 



Bigmutoferrite. A. Frenzel. J. pr. Chem., II., iv. 355. This name has been given to 

 a so-called hypochlorite from Schneeberg, having H. =1-2. G-. =4'47, and containing Si 23*08 

 F*e 33-33, Bi 43 - 26=99-67. Frenzel further distinguishes two varieties of hypochlorite, 

 (mtim&ny-hypocJdorite from Braunsdorf, and bismuth-hypochlorite from Schneeberg; both of 

 these are stated to be mixtures, and not homogeneous minerals. 



189. Chrompicotile. T. Petersen, J. pr. Ch., cvi. 137. 



A variety of chromite occurring in rounded octahedrons. H=8. G. =4115. Lustre vit- 

 reous to greasy. Color black. Analysis by T. Petersen and K. Senf ter (1. c. ) afforded : 



<Sr Si Fe Mn Co, Ni Mg 



5654 12-13 1801 0-46 tr. 14-08=101-22 



This composition does not differ much from that of the magnesian alumina chromite from 

 Baltimore, analyzed by Abich (Anal. 3. 4, p. 153), and that from Lake Memphramagog, 

 examined by Hunt. If this variety is to have a new name it should have reference to chro- 

 mite rather than picotite, a magnesia iron alumina spinel with only 7 per cent, of chromic 

 oxyd. Its hardness is the chief character which favors its being classed with picotite. 



From Dun Mountain, New Zealand. 



554 C. Coeetjleolactite. Cceruleolactin, T. Petersen, Jahrb. Min., 1871, 353. 



Crypto-crystalline to micro-crystalline. Fracture uneven to conchoidal. H.=5. Gr.=: 

 2*552 — 2*593. Color milk-white passing into light copper-blue. Streak white. Composi- 

 tion: AP, P- + 10 H=P 36-74, A-l 39-37, H 2329. Analysis by Petersen (1. c.) : 



P" Si £e Cu Zn Ca Mg gi F H 



3633 35-11 0-93 140 tr. 241 020 1*82 tr. 21-23=99-43 



Excluding the iron (supposed to exist as limonite), the silica, and copper, lime and magnesia 

 with sufficient phosphoric acid ( = 3'27 P) to make an ortho-phosphate, and calculating the 

 remaining constituents (89*26 \>. c.) up to 100 we have for the true composition of the min- 

 eral, according to Petersen, P 37 - 04, Al 39-34, H 23'62, corresponding very closely with the 

 above formula. B. B. decrepitates, infusible, on charcoal turns reddish-gray. With cobalt 

 solution gives a deep blue. Moistened with sulphuric acid colors the flame green. With 

 the fluxes gives a* faint reaction for copper. Soluble in mineral acids, also in fixed caustic 

 alkalies. 



From the Rindsberg Mine near Katzenellnbogen, Nassau. 



