G. J. Brush on Triphyline at Norwich, Mass. 



Art. XXXVIIL— On the occurrence of Triphyline at Norwich, in 

 Massachusetts; by George J. Brush. 



It is well known that a crystallized phosphate of manganese, 

 iron, and lithia was found by Hitchcock and Hartwell, associa- 

 ted with the spodaraene from Norwich, Mass., and that the crys- 

 talline form, and chemical composition of this substance have 

 been investigated by several mineralogists and chemists. Prof. 

 Dana and Mr. Craw* have shown this phosphate to be near 

 triphyline, although, as Mr. Craw states, "the results of his in- 

 vestigation tend to prove a wide difference from that species 

 rather than an identity with it." Prof Shepardf refers the min- 

 eral to triplite, and calls attention to the circumstance that Mr. 

 Craw's analysis connects the mineral with Damour's alluaudite 

 rather than with triphyline. Dr. Mallett's:|: analysis does not 

 differ essentially from that by Mr. Craw, and all these writers 

 agree in considering the substance as an altered mineral. 



Quite recently I have received from Prof E. Hitchcock, Jr., 

 some specimens which afford a solution of the question as to the 

 character of the original mineral. Externally the specimens have 

 an iron-black color; on the fracture, however, this iron-black 

 substance is shown to be a mere crust, having but an imperfect 

 cleavage, and passing gradually into a distinctly cleavable green 

 mineral, which occupies the centre of the crystal. On exam- 

 ination, this central mass proves to be identical with triphyline, 

 as will be seen by the following physical and pyrognostic char- 

 acters: cleavage distinct in two directions, one quite perfect; 

 color grayish-green, in thin fragments translucent ; streak white; 

 lustre vitreous inclining to greasy. H. = 5. Sp. Gr. = 3-534. 

 Heated in the closed tube decrepitates, blackens, and gives a 

 faint trace of moisture. On charcoal fuses readily to a black 

 magnetic globule. In the forceps fuses, blackens, and m the 

 outer flame gives reactions for lithia and phosphoric acid ; m 

 the reducing flame becomes magnetic. Fused in a glass tube 

 with sodium yields a phosphid, which on treatment with water 

 gives copious fumes of phosphuretted hydrogen. Dissolves la 

 borax, soda, and salt of phosphorus, reacting for iron and man- 



These characters are identical with those of the triphyline from 

 Eabenstein in Bavaria, and the source of the altered phosphates 

 of manganese and iron found at Norwich is thus shown to be 

 triphyline. This fact is also of further interest, as being the firs' 

 time that triphyline has been identified as occurring in this 

 country. 



Sheffield Laboratory, Tale College, Oct, Uth, 1862. 



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