326 i\Ir. T. S. Hunt's Examinations of some Canadian, Minerals. 



03g^xo adJ [f ■ AkiiniiMBa adi moVt bus ,Jr iJ9;fi!G^i«ii« ojolad ;f£xl-) 

 aq^i 9[b Oj Lime- !:rrot)i;;i ,'.af)ix: • . 1]'42 '-. jdi io 



fliiri Y^ O'u, Perositle of iiidnfi lui «. . "36 ,'0'i8 



odi Da '^" Magnesia i^adiao . . . trace ' i 



sqa g; Soda . ri ofU itii . . , 2-44 



Potash . . \ . . . -23 



'([ Water -40 



99-35 

 From the invariable loss on ignition, even when every precau- 

 tion has been observed in the desiccation of the minerals, I am 

 inclined to believe with Delesse and Laui'ent, that these small 

 quantities of water so generally met with in the felspars are 

 not hygroscopic, but belong to the chemical composition of the 

 minerals themselves. 



Raphilite. — This species was instituted some years since by 

 Dr. Thomson from specimens from Lanarck C.W., sent him 

 by Dr. Holmes of Montreal, and is, according to his analysis, an 

 anhydrous silicate of lime, magnesia, alumina and protoxide of 

 iron, with more than 10 per cent, of potash*. Dana, in the first 

 edition of his Mineralogy, suggested that it might be a fibrous 

 hornblende analogous to Arfvedsonitc, to which species Shepard 

 also refers it ; while in his last edition, Dana, in conformity with 

 the suggestion contained in my report for 18i7-^i8, regards it 

 as tremolitc. Being furnished with undoubted specimens of the 

 mineral, I have submitted it to a careful examination, the resrdt 

 of which confirms this opinion. 



It occurs in delicate fibrous masses slightly divergent, and 

 often several inches in length ; the fibres are readily separable, 

 brittle, and somewhat elastic. Hardness 5-5 ; Thomson gives 

 3" 75, but the fibres scratch deeply the s\irface of a crystal of 

 apatite. Specific gi-avity in powder 2*84-5 (2'850 Thomson). 

 Lustre vitreous silky ; colour grayish or greenish white, becoming 

 reddish on weathered surfaces ; translucent. Analysis failed to 

 detect more than veiy small portions of alkalies, and gave — 

 iu> Oxvgen ratio. 



Silica, on-clf . . 55-30 28-7182 = 2 



Lime. ... . 1336 37991 



Magnesia . . . 22-50 8-7162 



Protoxide of iron . 6-30 1-3982 

 - Alumina. '"^■'V "^-^ ?«i^^9«^''i viaf^g^orn.tnoq'isg ssu 

 '' Manganese .''''."''. traces'.' 



*• Potash .... -25 -0424 



Soda -80 -2064 



Loss on ignition . -30 143492 = 1 



99-31 



* Outlines, vol. i. p. 153. 



