50 MINERALS AND GEOLOGY 



small capitals. Names in ordinary type, refer to minerals of rare occurrence, or obscure 

 character : so far, at least, as regards the presence of these minerals in Canada. The initials 

 BB, signify "before the blowpipe." The number placed within brackets after the name of a 

 mineral, refers to the position of the substance in the classification proper, in which its des- 

 cription is given, at the end of the key 



( Aspect metallic or sub-metellic 2 



| Aspect non-metallic (i. e. vitreous, stony, &c. ) 35 



2 ( Occurring in detached grains or scales 3 



| Occurring under other conditions 6 



o j Soiling, or marking on paper GRAPHITE No. 1. ). 



| Not marking or soiling , 4 



. ( Yielding by trituration a white or light-grey powder. .MICA (Nos. 77-78.) 

 ( Not yielding a white powder by trituration . 5 



Colour, yellow. Fusible Gold (No. 3. ) 



Colour, tin or greyish white. Infusible Platinum (No. 4. ) 



Colour, black ; magnetic MAGNETIC IRON SAND (No. 31.) 



[Also Iserine (No. 32) 



Hardness sufficient to scratch glass 7 



Hardness insufficient to scratch glass 15 



( BB, emitting fumes, or odour of garlic or brimstone 8 



| BB, no fumes or odour 10 



Colour, light brass-yellow 9 



Colour, tin- white or greyish ARSENICAL PYRITES (No. 22. ) 



In cubes or other Monometric Crystals (p. 14), or massive 



IRON PYRITES (No. 20.) 



In pointed, Prismatic Crystals of the Rhombic System (p. 16,), mostly 

 arranged in curved rows Marcasite or Prismatic Pyrites* (No. 21.) 



10 ( BB, easily fusible Wolfram (No. 39. ) 



| BB, infusible, or nearly so 11 



j Streak-powder, dull-red SPECULAR IRON ORE (No. 29. ) 



j Streak powder, black or brown 12 



12 , Strongly magnetic MAGNETIC IRON ORE (No. 31.) 



' ' Not (or very feebly) magnetic ; 13 



13 



Streak, black, brown, reddish-brown, or greenish 14 



Streak, brownish-yellow. Yielding water in the bulb-tube ... 



BROWN IRON ORE (No. 34.) 



( Black, sub-metallic. BB, with phosphor-salt in R.. F., a fine greeu glass 



14 * CHROMIC IRON ORE (No. 33.) 



( Black, sub-metallic. BB, with phosphor-salt in R. F., a red-brown glass 



TlTANIFEROUS IRON ORE (No. 30.) 



, - ( More or less distinctly malleable 16 



10 j Not malleable " 20 



, * \ BB, no fumes, or deposit on charcoal 17 



/ BB, copious fumes, or incrustation 011 charcoal 18 



* Iron Pyrites and Marcasite have exactly the same composition (Sulphur 53.3, Iron 46.7) 

 but their crystal forms are quite distinct. Iron Pyrites is very abundant : Marcasite, in Canada,, 

 comparatively rare. Marcasite is especially prone to decomposition ; specimens are thus often, 

 ooated wit a greenish-white efforescence, or minute hair-like crystals, of sulphate of iron. 



