MINERAL RESOURCES OF BRITISH NORTH AMERICA. SKETCH OF THE NATURE, EXTENT AND VALUE OF THE METALS AND OTHER BY CHARLES ROBB, MINING ENGINEER, MONTREAL. INTRODUCTORY REMARKS. CANADA is emphatically an agricultural country, and is pre-eminently favored by nature in the excellence of its soil, and the adaptation of its climate to the growth of wheat and the other cereals, which must long continue as heretofore to constitute its staple productions. Its natural resources, however, are by no means limited to the vegetable kingdom; and although, in the earlier stages of its history, the products of its fields and forests naturally occupy the greatest attention, and have received the fullest development, the extent and importance of the mineral treasures with which it abounds are now beginning to be duly recognized. With the exception of coal, and a few of the less important metals, Canada has been found to produce almost all the known useful minerals; while, with regard to most of them, it may be safely asserted that she contains within herself a supply not only amply sufficient for her domestic consumption, but for permanent, profitable and extensive foreign commerce. These boundless sources of wealth have as yet been rendered available only to a very limited extent, owing partly to the fact of their existence having been so recently brought to light, and partly to the want of the capital and skill requisite to develop them. As the resources of Canada are now rapidly becoming known to the rest of the world, and as it is gradually learning greater selfreliance, it may be reasonably expected that its mineral productions are destined to assume their due rank in contributing to the national wealth and prosperity. In relation to this department of the contribution made by Canada to the Great Exhibition of 1851 at London, the following judgment was pronounced by the jury: "Of all the British colonies, Canada is that whose exhibition is the most interesting and complete, and one may even say that it is superior, as far as the mineral kingdom is concerned, to all countries that have forwarded their productions to the Exhibition." This judgment will doubtless be more than confirmed by the results of the Great International Exhibition of 1862, to which Canada has contributed a collection of minerals far in advance of that of 1851. We have stated that coal does not occur in Canada, and we fear it must be regarded as a fully established fact, at least in regard to those parts of the country which have as yet been settled and explored. The rocks are throughout of a lower geological horizon than the carboniferous; and although bituminous schists and shales abound, and thin veins of a substance closely resembling coal occur in cer tain parts of the country, these can not be regarded as of much economic importance. Canada is, however, very favorably situated in its proximity, at all points, to the carboniferous regions of the United States and Nova Scotia, and in the facility of conveyance afforded by its vast lakes, rivers and canals; and moreover, it contains within itself such ample supplies of wood, peat and mineral oil as will go far to compensate for the want of coal. Many useful minerals yielded in abundance by Canada, and which require peculiar chemical treatment to render them available in the arts, such as chromic iron, phosphate of lime, petroleum, &c., are rendered comparatively valueless from the fact, that in present circumstances, the crude material has to be transported at great expense to distant manufacturing centres. Such materials are peculiarly deserving of the attention of enterprising capitalists, as their manufacture in the province would be attended with the double advantage of rendering them available as a source of national wealth as well as individual profit, and of giving employment to an industrious and intelligent class of population. The knowledge we possess of the mineral wealth of Canada, imperfect as it necessarily is, from the vast extent of unexplored and partially explored territory, as well as from the recent date at which public attention began to be directed to the subject, is nevertheless sufficiently accurate to admit of a certain classification and arrangement, and the geographical distribution of the various useful minerals has been ascertained with considerable accuracy. For much or nearly all of this knowledge we are indebted to Sir William Logan, the Provincial Geologist, and his coadjutors, who have devoted themselves assiduously, (under the liberal patronage of the Provincial Government,) during nearly twenty years to the investigation of the Geology of Canada; and whose labors have not only conferred incalculable benefit on the country, but procured for themselves a worldwide reputation. In order to illustrate our remarks upon the mineral productions of Canada, we shall give a slight sketch of the geological structure of the country as ascer tained by the provincial geologists. GEOLOGICAL STRUCTURE OF CANADA IN RELATION TO ITS USEFUL MINERALS. The oldest geological formation in Canada, styled by Sir William Logan the Laurentian system, occupies all the northern and portions of the central divisions of the province, extending over an area of about 150,000 square miles, and composed of various hard rocks, such as gneiss and white crystaline limestone; the total thickness of this formation in Canada is probably not less than 20,000 feet. These rocks consist of highly altered strata, in which no positive and unequivocal traces of organic life have been as yet detected; and which have been bent, twisted and tilted up at all angles, and in some places invaded by masses of intrusive rock. Among the useful minerals peculiarly characteristic of this formation, the ores of iron are the most important, being found in interstratified layers or beds in quantities which may be regarded as inexhaustible and of exceedingly rich quality. Veins of lead and copper also, cutting the stratification, occur in the formation, especially at or near its junction with the next succeeding system of rocks; plumbago and mica abound, and phosphate of lime and sulphate of barytes are of frequent occurrence. The Laurentian limestones furnish marbles of very excellent quality, together with a great variety of materials applicable to ornamental purposes. The Huronian system, the next in ascending order, is wanting in the eastern and central parts of Canada, but attains a great development on the northern shores of Lake Huron and parts of Lake Superior; occupying a linear extent of about 400 miles, and consisting of slates, altered sandstones, limestones and conglomerates, associated with heavy masses and dykes of trap; the total thickness is esti mated at about 18,000 feet. This system constitutes what has been called the lower copper-bearing rocks of the lake region; the ore occurring sometimes disseminated among the slates, but more frequently in quartz veins intersecting them. These deposits of copper ore have formed, for many years back, the object of mining operations; and there can be no doubt that this region contains metallic treasures which will one day become the source of great wealth to Canada. In addition to copper, silver and nickel occur in this formation in quantities which promise to be of economic importance. Agates, jasper and other varieties of precious stones are of frequent occurrence, and the jasper conglomerate, which abounds in this region, affords a beautiful material, which will be found applicable to many purposes of decorative construction. The upper copper-bearing rocks, including the wellknown rich deposits on the south shore of Lake Superior, have recently been discovered to have their equivalents in what has been denominated the Quebec Group, in the eastern part of the province; consisting of altered and highly dislocated and disturbed limestone and sandstone strata, belonging to the inferior part of the Lower Silurian system, and extending in a belt varying from twenty to sixty miles wide, from the borders of Lake Champlain eastward to nearly the extreme point of Gaspé. This important region, which occupies an area of over 15,000 square miles, is a portion of the great metalliferous formation of North America, which includes the well-known mining regions of the Appalachian chain from Canada to Tennessee, as well as those of Missouri and the Lake Superior region. Although this fact has but recently been recognized, many valuable discoveries of copper and other metals have already been made in the eastern townships of Canada, and at other points comprised within the region specified. In addition to the metals, it abounds in roofing slates of excellent quality, besides many beautiful varieties of serpentine, marble, soapstone, whetstones, ochres, &c. The central portion of the province, comprising the region bordering on the north shore of Lake Ontario, and ex tending over an area of about 7,000 square miles, is under laid by rocks of the Lower Silurian age, which are comparatively unaltered, both as regards position and chemical |
