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XLVI. Contributions to the Miner alogij of Nova Scotia. By 

 Professor How, D.C.L., University of King's College, Windsor, 

 Nova Scotia. 



[Continued from vol. xxxi. p. 170.] 



II. 

 YMflCHTYNE. — A mineral which I refer to this species was 

 brought to me by a farmer from Cornwallis, King's co., 

 where it had attracted attention as something possibly valuable, 

 and was known as {i little pebbles/' a name which, in the absence 

 of information upon the geological situation of the mineral, gives 

 some clue as to the mode of its occurrence. What I received 

 consisted of several small pieces, either rounded and bean-like 

 with smooth dull surfaces, or irregular in form with angular 

 prismatoidal outline and of lustre somewhat glassy. This lustre 

 was much more distinctly seen on breaking the pieces ; these were 

 brittle, and had a conchoidal fracture. The greatest hardness 

 observed was about 7*5 ; the specific gravity in three experiments 

 was respectively 2'775, 2*815, and 2'881, the mean of which 

 numbers is 2*823. In colour it was indigo-blue, blue-black, and 

 greenish black with a grey tint in some parts ; the streak and 

 powder were white. Before the blowpipe, fragments frothed and 

 fused to a dark enamel. As might be expected from the differ- 

 ences in colour and the varying specific gravity, the composition 

 of the " pebbles'''' is not uniform : the constituents appear to be 

 the same; but their relative proportions are not constant, as is 

 shown by the following analyses which were made by fusion with 

 carbonated alkalies for the constituents other than potash and 

 soda, these being estimated after treatment with fluor-spar and 

 sulphuric acid. The iron was found to exist both as peroxide 

 and protoxide, the latter being by far the more abundant ; no 

 attempt, however, was made to ascertain the exact relative pro- 

 portions on the small amount of mineral in my possession. The 

 nature of the alkalies present was made out by fusion with car- 

 bonate and chloride of barium and subsequent testing with bi- 

 chloride of platinum dissolved in strong alcohol. The results 

 obtained were — I. n. m. 



Silica 56-85 57'47 55-12 



. Alumina 11-53 15-17 



Protoxide of iron* .-'. .. 14-79 16-62 



Protoxide of manganese . .. 057 0'19 



Lime 2-01 5-12 



Magnesia 7'21 3*33 



Water 0-62 



Potash and traces of soda. . . . . 3 '03 



98*58 

 * Iron really found in small part as Fe 2 O 3 . 



