occur in Damaraland, and constitute the diamond fields of German West Africa. The diamonds occur on the surface, and can be picked out by hand; they have all been, so far, of small size.
The platform on which the Karroo, Cretaceous, and Recent deposits rest is divided into two sedimentary series, which can be illustrated by the following table:—
Nama Formation. |
Hanami or Fish River sandstones | = | Waterberg System. | |
Green shales and light sandstones | = | Pretoria Series. | ||
Otawi limestone | = | Dolomite Series. | ||
Huib or Kuibis quartzite | = | Black Reef Series. | ||
Primary Formation. |
Chanse greywacke. | |||
Orange schists, green schists, quartzites, and limestone. | ||||
Komas schists, thinly foliated gneiss, mica schist, limestone. | ||||
Granite and Gneiss. |
The only series of which the correlation at present is tolerably certain is the Dolomite, which, being a deep-water deposit, was more constant in its characters; the more littoral deposits of the Black Reef Series would naturally tend to vary more.
RHODESIA
Rhodesia consists of a great tableland of granite, through which are drawn bands of schists folded in narrow belts in the granite. Remnants of the Dolomite Series and overlying Waterberg Sandstone are found near the Limpopo and near the Zambesi, but for the rest of the country none of these formations remain. A vast area of the country, however, is covered with Karroo Beds, with coal and the Forest Sandstone, which is the same as the Cave Sandstone, and in the north great