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colour of streak, structure, or other easily determined character. In this manner
we arrive, without difficulty, at the name of our mineral.
To illustrate this by example, let it be supposed that we have a piece of a red, dull, and somewhat earthy-looking substance, the name of which we wish to ascertain. By its non-metallic aspect, we see at once that it belongs either to group C or to group D. We try if it will scratch glass. It is not sufficiently hard to do this : hence it belongs to group D. Turning now to the respective sub-groups or sections under D, we find that our mineral has no taste, and hence does not belong to Dl. Neither does it take fire (although it blackens) when a thin splinter of it is held for a moment in the flame of a candle, or in the Hame of an ignited match : and hence it does not belong to D 2. It has, however, a coloured streak* (red), and so belongs to the next section, D3 Now in this section there are only two minerals with red streak: or only one, indeed, of undoubted Canadian occurrence - Earthy Red Iron Ore, commonly called Red Ochre; and as our mineral becomes magnetic after exposure to the flame of a match or candle, it can be nothing else than a specimen of that substance. This example will be sufficient to shew the method of procedure to be followed in order to ascertain the name, &c, of an unknown mineral, by reference to the annexed TABULAR Distribution. In this connexion, it has been thought advisable to include a few substances of more or less common occurrence in the United States, although not yet found in Canada ; and also to refer occasionally, in smaller type, to some other minerals of economic value or popular interest, so as to make the subject more complete, and render our Tables available for the examination of the small collections sometimes imported into this country for the purposes of study. Some of the substances thus noticed, may also be discovered eventually in Canada. Finally, it should be observed that the descriptions of these various minerals, given in our TABULAR DIST.IBUTION, are necessarily exceedingly brief, referring only to matters of easy comprehension or general importance. When, however, the name of a mineral is once discovered, the reader, if he desire to pursue the subject further, can refer for fuller details to any of our ordinary works on Mineralogy.
• For an explanation of these characters, technical terms, &c., see Part I.
A TABULAR DistriBUTION OF CANADIAN MINERALS, INCLUDING, ALSO,
OTHER MINERAL SUBSTANCES OF
The reader is to determine, by this Index, the group and sub-group to which his unknown mineral belongs ; and he is then to refer to the descriptions given under that sub-group in the pages immediately following the Index.
Hard enough to scratch glass Aspect Metallic
Not hard enough to scratch glass .. B. S
4. Aspect metallic. Hard enough to scratch glass :
Fusible. Yielding water in the bulb-tube (fig. 22). .. C 4.
scratch glass :
.. D 2.
A. Aspect Metallic. Hardness sufficient to scratch glass.
A 1.-Colour, Light Brass-yellow. Iron Pyrites.-A substance of a pale brass-yellow colour, with greyish-black streak, occurring in amorphous, globular, and other masses, and in Monometric crystals (cubes, generally with alternately-striated faces, pentagonal dodecahedrons, &c., figs. 23, 24, 25.)
H. 6.0-6.5; sp. gr. 4.8–5.1. Fusible, with sulphur fumes, into a magnetic globule. One hundred parts contain: sulphur, 53-5 ; iron, 46.7 ; but the iron is sometimes in part replaced by a little cobalt or nickel, and occasionally minute portions of gold and silver are accidentally present. Iron pyrites occurs in all kinds of rocks, and is exceedingly common ; but is useless as an ore of iron. It yields copperas, or iron-vitriol, by decomposition; and it is often converted on the surface, or wholly, into hydrated brown oxide of iron. It sometimes forms the substance of organic remains, as in many of the Trilobites, &c., of our Utica Slate. Amongst the principal Canadian localities, we may note, more especially, the counties of Pontiac (Clarendon Township), Terrebonne, Berthier (Lanoraie Seign.), and Sherbrooke (Garthby Township), in Canada East; the vicinity of Balsam Lake, where it occurs with magnetic pyrites; and many places on the north shore of Lake Huron, Lake Superior, &c. A nickeliferous variety occurs in D'Aillebout, Berthier Co.; and an auriferous variety in Vandreuil, Beauce Co., C. E. We have obtained some brilliant, though small, crystals from the white feldspathic trap of the Montreal Mountain ; and also from the Niagara limestone, and other fossiliferous
*For the localities mentioned in these descriptions, we are very largely indebted to the publications of the Canadian Geological Survey, and espeecially to the Esquisse Géologique du Canada, by Sir W. E. Logan and T. Sterry Hunt. We shall be greatly obliged to our readers for any information respecting localities of Canadian minerals; and more especially, if a small fragment of the substance referred to in the information, be furnished at the same time. A piece no larger than our ordinary pea will be of sufficient size. Although we are constantly receiving specimens of different kinds for examination, the exact localities of these are generally kept secret by the senders, in the belief that something has been discovered of more than usual value.
rocks; but iron pyrites occurs chiefly in our Laurentian and Huronian Formations, and in the Metamorphic district of the Eastern Townships. The general reader will find these geological terms fully explained in some of the succeeding papers of this series. Radiated Pyrites, or Marcasite, also belongs to this Section, but it does not
appear to have been noticed in Canada. It has the same composition as common Pyrites, but crystallizes in the Trimetric or Rhombic System. Many globular specimens, with radiated s'ructure, sometimes referred to Marcasite, belong truly, it should be observed, to common Pyrites.
A. 2.- Colour, Pale Copper Red (usually with grey or black external
tarnish.) Arsenical Nickel. Pale copper-red, tarnishing dark-grey. Streak, brownish-black. Chiefly in small amorphous masses. H. 5.0-5.5 (it scratches glass feebly.) Sp. gr. 7.3-7.7 (a salient character.) Fusible, with strong odour of garlic. One hundred parts contain: Arsenic, 56; Nickel, 44. This substance, often called Copper-Nickel from its copper-red colour, is the common ore of nickel ; but in Canada it is very rare.
It has been found in small quantities in Michipicoten Island, Lake Superior. A substance composed of sulphur, arsenic, and nickel, occurs likewise, but in very small quantities, at the Wallace Mines, Lake Huron. It is somewhat less hard than Arsenical Nickel. The Townships of Bolton and Ham, in the metamorphic district of the Eastern Townships, are also cited as localities of nickel ore. The ore is said to occur there very sparingly in Serpentine, associated with Chromic Iron Ore.
A. 3. Colour, Tin or Silver-white (sometimes with grey or yellowish
external tarnish.) Arsenical Pyrites (Mispickel.)—Tin or silver-white, inclining to light steel grey. Streak, greyish-black. In amorphous and granular masses, and in modified rhombic prisms (Trimetric System.) H. 5.5-6.0; Sp. gr. 6.0-6.4. Fusible, with garlic odour, into a magnetic globule. One hundred parts contain: sulphur, 20; arsenic, 46; iron, 34. This mineral is of very common occurrence in many countries. It is quite useless as an ore of iron, but is employed in Germany and elsewhere in the production of arsenious acid, the white arsenic of commerce. Arsenious acid is obtained also, and more abundantly, from arsenical nickel and certain cobalt ores. In Canada, arsenical pyrites occurs in small quantities with common iron
pyrites, &c., in our azoic and metamorphic rocks more especially, at various localities : as at the Lake Huron Mines; in Clarendon Township (Pontiac Co.); in the Chaudière Valley, &c. It sometimes contains a little cobalt, in which case, after exposure before the blow-pipe to drive off the greater part of the arsenic and sulphur, it fuses with with borax into a rich blue glass.
The common cobalt ores (Smaltine and Cobaltine) belong also to this Section, but they bave not yet been discovered in Canada.
A 4. Colour, Steel-grey, Iron-black, or Brown. (No fumes before
the Blow-pipe.) [Principal Minerals.—Streak, dull-red: Specular Iron Ore. Strongly magnetic;
streak, black: Magnetic Iron Ore. Yielding water in the bulb-tube; streak, yellowish-brown: Brown Iron Ore.]
Specular Iron, or Red Iron Ore.—Dark steel-grey, often inclining to blueish red. Streak, dull-red, the same as the colour of the earthy varieties described in Section D 3. In rhombohedral crystals and crystalline groups, and in lamellar, micaceous, and fibrous-botryoidal masses, the latter often called Red Hæmatite.
H. 5.5-6.5 ; sp. gr. 4.3–5.3. In thin splinters, fusible on the edges (although commonly said to be infusible.) Becomes also magnetic after exposure to the blow-pipe, and is often feebly magnetic in its normal condition. One hundred parts contain : Oxygen, 30; Iron, 70. This mineral is one of the most valuable of the Iron Ores. In Canada, it is exceedingly abundant, more especially in our Laurentian rocks,, although less so than the Magnetic Iron Ore. It occurs chiefly in these rocks in the Township of MacNab, on the Ottawa, where it constitutes a vast bed, twenty-five feet thick, in crystalline limestone ; and also associated with crystalline limestone at Iron Island, Lake Nipissing (Mr. Murray.) In the Huronian rocks, it is found at the Wallace Mine, Lake Huron ; and it occurs likewise in metamorphic chloritic schists (altered Silurian shales of the age of the Hudson River group), associated with magnetic iron ore, dolomite, &c., in the Eastern Townships of Sutton, Bolton, and Brome.
Ilmenite. This substance, (normally, perhaps, a compound of the sesqui-oxides of titanium and iron,) has an iron-black or dark steelgrey colour, with black or dark reddish-brown streak. It closely resembles and passes into Specular Iron Ore. At Baie St. Paul, C.E., a large deposit of Ilmenite, three hundred feet in length and ninety feet broad, occurs in a feldspathic rock of the Laurentian series. It is