Geochemical analyses of 102 samples are reported from the 25 largest intrusive bodies of the Gamsberg, Piksteel and Weener Intrusive Suites within the Rehoboth basement inlier. It is shown that all the analysed granitoids are peraluminous and that they plot on calc-alkaline differentiation trends. The high alumina saturation of most of the analysed samples suggests an upper crustal origin for most of the Gamsberg, Piksteel and Weener magmas.