Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/168

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If we take a vertical section of the Natal formations, we shall find them as follows : —

Brown soft sandstones and grit, with great Cretaceous Series, Lower Greensand numbers of fossils. up to White Chalk.

Sandstones and shales, with coal-beds, Karoo formation: probably Trias, shales, and Boulder-bed (greenstone reaching as far up as the Jura. dykes).

Quartzose sandstone with shales ; containing Table-Mountain Sandstone. Coal- only traces of fossil remains. period.

Clay- and talcose slates, mica-schists, dykes Primary slate-formation. of diorite.

Granite and gneiss, dykes of diorite. Primary rocks.

III. Economic Geology.

Industry and the fine arts are still in their childhood in Natal ; otherwise the raw materials are there in abundance. Natal possesses good building-material in the quartzose sandstone of the Table Mountains, and an excellent slate which is found at some places (for instance, at the Umpampinioni river). The lower parts of the crystalline limestone would, I have no doubt, afford a good statuary marble.

1. Graphite. — A very good quality of pure graphite is found south of Springvale, in Natal — in gneiss, as it seems. As the working of the graphite is not expensive, a ton of pure graphite costing only about £30, it would probably be a lucrative undertaking to ship graphite at Durban. Graphite is not very rare in South Africa ; traces of it are found at several points in the " old colony." A considerable amount of this mineral is to be met with, as I have been informed not very far from the Mission-station of Inyatin, about 20° S.

2. The Coal of Natal, which belongs to a younger series than the more newly discovered one near Tulbagh, in the Cape Colony, seems to form extensive fields in the sandstone and shales of the plant- bearing Karoo formation. Although it is a good steam-coal, it is still cheaper to import the coal from England or Australia, whence it may be obtained at 27-55 shillings the ton at Durban.

3. Metals. — a. Gold. Every body remembers the great excitement which was caused by the first " discoveries " of gold in South Africa. Since then companies have been formed, shares sold and bought, diggers have been sent out, and the colonies hoped for better days ; but suddenly the gold-fields turned out to be imagination, as it became pretty certain, and indeed an ascertained fact, that gold was not in sufficient quantities to pay the working of the quartz. Not only in the interior, but also near the coast, within the boundary of the colony, gold was sought for. Traces of gold are to be seen in the quartz-veins and quartz masses (" reefs ") in the granitic and slate- formation, but not sufficient to pay the expense of crushing. I have visited most of the localities in Africa which were called auriferous ; but nowhere did it seem to me likely that it would pay for working, as the quartz-veins (supposing they would yield a paying quantity)