ouklipn.

1892 Jrnl. (Graham's Town, S. Afr.) 20 Sept. 2 A few months ago it was discovered..that large beds of Ou Klip (honeycomb gravel rock) on the farm were literally saturated with mercury.

1940 Min. Resources Union S. Afr. (Dept. of Mines) (ed. 3) iv. 458 There are many types of laterite or ‘ouklip’ in this country. The harder types of conglomerate ouklip generally form a very good basecourse for bitumen.

1955 J. H. Wellington S. Afr. I. ii. x. 289 In the western highlands of Natal, Peutz recognizes a third grassveld type..in which the infertile sandy soils, underlain by ‘ouklip’ (i.e. pirolitic ironstone) produce a poor type of veld.

1961 M. M. Cole S. Afr. iv. 87 The weathering processes..result in the formation of soils comprising an A horizon of some 12 to 24 inches of friable sand..overlying a B horizon of mottled clayey-sand containing many ferruginous concretions which in the lower part are cemented to form a hardpan called ‘ouklip’.

1973 Farmer's Weekly 9 May 65 The presence of ‘ouklip’ layers just under the surface of a soil means poor drainage and gives rise to ‘drowning’ of plants in wet seasons.

1988 D. Hughes et al. Compl. Bk. S. Afr. Wine (ed. 2) 55 Kroonstad has a sandy top layer with an iron-bearing pan of peculiar hard, nuggety forms known as ouklip just above the clay.