500 DescripHon and Analysis of two Mineral Species. 



collection of the Canadian Institute, the cleavage prism is appa- 

 rently right rhomboidal; the inclination of M : T = 110°to 115°. 

 The cleavages with M and P are perfect, and easily obtained, 

 giving to the mass a fibrous aspect -, with T the cleavage is im- 

 perfect. Hardness, 3'5; density, 2-765 to 2-776. Lustre vitreous, 

 shining, occasionally pearly on the cleavage surfaces. Colour, 

 rose-red to peach-blossom red ; subtranslucent ; fracture uneven. 

 Before the blowpipe it becomes white and opake from the loss 

 of water, and fuses easily with intumescence into a white enamel. 

 When pulverized and boiled with hydrochloric acid, it is partly 

 decomposed with separation of pulverulent siUca. A qualitative 

 analysis showed the presence of silica, huie, magnesia and 

 alumina, with a little iron and traces of manganese, besides a 

 large quantity of potash. The results of three quantitative 

 analyses are subjoined ; the earthy ingredients were determined 

 by fusion with carbonate of soda; the alkalies in the first ana- 

 lysis were separated by a method for which I am indebted to 

 Dr. A. A. Hayes of Boston. It consists in fusing the pulverized 

 mineral for half an hour with one part of pure lime and four 

 parts of chloride of calcium in a platinum crucible ; the fusion 

 was eflPectcd over a spirit-lamp. When cold, the mass was di- 

 gested with water, and the solution then contained all the alkalies 

 as chlorides, mixed with chloride of calcium. The lime-salt was 

 decomposed by carbonate of ammonia, and the sal-ammoniac 

 separated by sublimation from the evaporated residue, leaving 

 the alkaline chlorides in a state of purity. The whole amount 

 of water in the mineral is only expelled by a heat which produces 

 incipent fusion. The small portion of silica, which in the ordi- 

 narv process of analysis adheres to the alumina, was not sepa- 

 rated except in the third of the following analyses : — 



I. II. III. 



Silica 42-90 43-00 43-55 



Alumina \28-10 27-80 27-94 



Oxides of iron and manganese J ... "70 '20 



Lime 6-94 6-72 6-50 



Magnesia 3-99 3-83 3-81 



Potash 8-27 8-27 8-37 



Soda -95 -95 1-45 



• Water 9-00 9-40 8-61 



100-15 100-67 100-43 

 As this interesting mineral appears to constitute a new species, 

 I have named it WiJsonite after its discoverer, Dr. Wilson, who 

 has long been known as a zealous student of the mineralogy of 

 his district. It is to be wished that further examinations may 

 detect distinct crystals of tlie mineral ; a single imperfect one 



