Samples of powdered quartz-mica schist (50 g) from Signy Island, South Orkney Island, were added to 50 ml of deionized water and shaken for 15 minutes to dissolve all soluble material. The aqueous solution was filtered under vacuum through a 4.0 mu m filter to remove any fine material in suspension, and 1 ml of conc. HNO3 was added. The resulting sample was analysed for Ca, Na, Mg, K, Si, Fe and ... [Show full abstract] Cu using an inductively coupled Ar plasma emission spectrophotometer. Sub-samples of the rocks were analysed for their porosity, water absorption capacity, saturation coefficient and microporosity. The data obtained provide a valuable guide to both the understanding of weathering processes (particularly freeze-thaw and salt weathering) on Signy Island, and to the salt concentration which should be used in the laboratory to simulate mechanical weathering. -J.M.H.