1853.] 297 



sulphuric acid was then passed through the solution, which precipitated sul- 

 phides of copper, of arsenic and of antimony. This precipitate was filtered and 

 treated with sulphide of ammonium. The remaining sulphide of copper was 

 oxydized by nitric acid, and the oxide precipitated by caustic potash. It gave 

 0.0512 grs. 



The solution containing antimony and arsenic was boiled with hydrochloric 

 acid and chlorate of potash, then tartaric acid, an excess of chloride of ammo- 

 nium and ammonia added, and the arsenic acid precipitated by sulphate of mag- 

 nesia as arseniate of magnesia and ammonia. From the quantity of magnesia in 

 this double salt the arsenic was found by calculation. The weight of magnesia 

 was 0.0082 grs. The filtrate from the sulphides of copper, arsenic and antimony 

 was oxydized by nitric acid, and the sesquioxide of iron precipitated by ammo- 

 nia; it was 0.0027 grs. ; the zinc was thrown dowii from the filtrate of iron by 

 sulphide of ammonium, and gave 0.0042 grs. oxide of zinc. 



Sulphur and antimony were determined from the loss, and by calculation. 



On Otoenite, a new Mineral. 

 By Dk. F. a. Genth. 



Formula 2(3RO, SiOj )4-(3R203, Si03)4-6HO. 



Massive ; aggregate of minute scales ; cleavage distinct in one direction. 



H. =2'5; Sp. Gr. (at 20 C) = 3-197; lustre pearly; color olive green; 

 streak paler ; very tough ; fracture subconchoidal ; the powder greasy to the 

 touch ; odor argillaceous. 



B.B. fuses easily = 3; and gives an iron-black magnetic globule; with borax 

 gives the reactions of iron, and with soda slightly those of manganese. Yields 

 water in the matrass. Dissolves in hydrochloric acid. 



3Ir. Peter Keyser has analysed it in my laboratory, and found the followino- 

 composition : 



Contains Oxygen. 

 12-05 



7-681 



X% \ 8-39 



0-11 ! 



0-01 J 



9-42 



99-872 100-060 



Found at Harper's Ferry, Virginia, in metamorphic rocks with quartz. It 

 has impressions of Dolomite. 



The name is given in honor of D. D. Owen, M. D., TJ. S. Geologist. 

 The ratio of the oxygen of RO : R^Og : Si03 : HO, is : 

 8-39 : 11-45 : 12-05 : 9-42 



1 : 1-36 : 1-43 : 1-12, or very near 

 1 : 1-50 : 1-50 : 1*00, corresponding with the formula 

 2 (3 RO, SiOg) + (3 R2O3, SiOa) -f 6 HO. 



The Owenite is closely allied to some other minerals, viz. Aphrosiderite and 

 Thuringite. All three resemble each other very much, and only by chemical 

 examination their difference can be detected. 



Aphrosiderite is a mineral not generally known ; found at several localities 

 in Nassau, and first distinguished from earthy chlorite by Fridolin Sandberger, 



