Page:Niger Delta Ecosystems- the ERA Handbook, 1998.djvu/160

The Resources of the Niger Delta: Minerals Sand can be viewed as a locally renewable resource because it is replaced by the rivers which bring it down stream, in its progress towards the sea, where much of it is swept back to form the beach ridges of the Delta coast.

14.8 SOIL AND CLAY

In the LEM ecozone where the soils are deep enough, soil, particularly if it has high clay contents, is dug for building up the foundations of roads, so that Borrow-pits are common sight.

Deposits of Kaolinite clay, found throughout the Niger Delta, are used by women for making clay pots. The Ogoni potters are particularly famous.

14.9 PERIWINKLE SHELLS

Periwinkle shells are a renewable mineral resource used as an especially good calcium aggregate for binding cement to make for concrete. In the Fresh and Brackish-water, and Sand-barrier Island ecozones there is no alternative.

14.10 SALT

Salt extraction from the Brackish-water ecozones of the Guinea, Ghana and the Benin Republic is extensive, which makes it all the more surprising that so little is extracted in the Niger Delta. It seems that the communities living around the mangrove forest prefer 'native salt' made from the charcoal of Rhizophora racemosa propagules. However, sea salt production occurs at Brass, where seawater is boiled on metal trays. 158