APPEXDIX. 



13 



218 E. Rabdioxite. F. von Kobetf, Ber. Ak. Miinchen, January 8, 1870. 



Stalactitic, in columnar or red-like forms. Very soft, soiling the fingers. G.=2'80. Lus- 

 tre dull, after rubbing is greasy to submetallic. Color black. Streak dark-brown. Com- 

 position : 



Fe Mn Si Cu Mn Co H 



4500 13-00 1-40 14-00 7-61 510 13-50=99-61 



The oxvgen ratio of R : H : H is 1 : 3 : 2, and v. Kobell writes the formula (Cu, Mn, Co) 

 (Fe, Sn) + 2 H. 



In the closed tube gives neutral water. B. B. fuses at 3 to a steel-gray, magnetic-globule, 

 and colors the flame green. With borax gives a cobalt blue bead. Soluble in muriatic acid 

 with evolution of chlorine, giving an emerald-green colored solution. 



From. Xisehne Tagilsk in Ural. The mineral is near asbolite (p. 181), but differs from it 

 in chemical composition, in containing a large percentage of iron, and in being easily 

 fusible. 



163 A. Ralstoxite. G. 7. Brush, Am. J. Sci., III. ii. 30. July, 1871. 



Isometric. Habit octahedral. Observed planes 1, O (this Min. fig. 7, p. 21). H. =4'5. 

 G-. =2 - 4 (on 25 milligrams). Composition, a hydrous fluorid of aluminum, with possibly smaU 

 quantities of calcium and sodium. 



In the closed tube whitens, yields water at first, then a copious white sublimate which 

 etches the tube. The water reacts acid. B. B. on charcoal a faint white sublimate. In the 

 forceps whitens, colors the flame yellow, but does not fuse. With cobalt solution gives a 

 deep blue. In salt of phosphorus dissolves completely to a colorless bead in both flames. 

 Soluble with effervescence in a carbonate of soda bead. Decomposed by sulphuric acid 

 with evolution of fluohydric acid. 



Occurs with cryolite and thomsenolite at Arksut Fiord, Greenland. 



Redondite. A name given by C. IT. Shepard to a hydrous phosphate of alumina and iron 

 from Redonda. W. I. Found in nodular aggregations. Translucent to opaque. Color gray- 

 ish to yellowish white. H.=3 - 5. G. =1'90— 2'07. Specimen analyzed contained 8 - 8 per 

 cent. Si. 40192 P and 2473 H (Am. J. Sci. II. 1. 96). An earlier analysis gave P 43-20, 

 Fe 1440. Al 16-60. H 24-00, Si 1-60, Ca 0.57=100 '37, contained also traces of S, Na, CI, 

 and Mg. B. B. infusible. Heated with solution of cobalt gives a deep blue color (Am. J. 

 3 . II. xlvii. 428. 



422. Bestormelite. A name given by A. H. Church (Jour. Chem. Soc, II. viii. 166) to a 

 massive grayish-green agalmatolite-like mineral from Restormel Mine in Cornwall. H. =2. 

 G.=2-58. Mean results of analysis gave Si 45-66, Si 35-10, Fe 111, Mg 0-85, K 2-30, Na 

 4 "39, II 11 -68=101 '09. This composition is near that given by Lehunt and Blythe for killi- 

 nite (anal. 29 and 30, under pinite, p. 481). Church does not consider the mineral worthy to 

 rank as a distinct species, but speaks of it as an " imnuilure kaolinite." 



261 A.. Roepperite. Iron, manganese, zinc, chrysolite. W. T. Boepper, Am. J. Sci., 

 II. 1. 35. Roepperite, G. J. Brush. <*r^- 



Orthorhombic. observed planes i-2, i-%, 1-2, i-%, 1-2, 1-4, O, 2-2. ^-2 A * : 2 (over i-%) 130°, i-% 

 / £-2=115 c 1-2 a 1-2=77°. Cleavage in three directions rectangular, O and i-% eminent, 

 /-' splintery. H. =5:5 — 6. G. =3 '95— 4-08. Lustre on cleavage planes vitreous to sub- 

 adamantine. Color dark-green to black, mottled. In thin splinters translucent and pale- 

 yellow color. Streak yellow to reddish-gray. Slightly magnetic. Composition : R- Si. R- 

 = Fe, Mn, Zn and Mg. Analyses 1. 2. 3., W. T. Roepper (1. c.) : 



Si Fe Mn Zn Mg Insol.* 



1. Cryst. 3076 33'78 1625 1096 760 =99"35 



2. Cryst. f 30-23 3552 1691 1068 5-63 1-04=100.01 



3. Mass. f 30-54 34'78 17-74 9"48 6"09 2-02=100'65 



* Spinel. 



B. B. fuses with difficulty on the thin edges to a black slag. With the fluxes reacts for 

 iron, manganese, and silica ; on charcoal with soda gives a zinc coating. Gelatinizes with 

 acids readily and completely, leaving sometimes a bright-green residue of spineL 



Occurs at Stirling Hill, Sussex Co., N. J., with willemite, franklinite, jeffersonite, and 

 spinel ; also found at Franklin Furnace with gahnite. 



