Tertiary sediments are the main source of construction sand and plastic clay for brickmaking for the Adelaide Metropolitan. A large area of similar sediments near Freeling, north of Adelaide were investigated in 2 stages involving: - 80 hole scout auger drilling, mainly W and NE of Freeling, - 15 hole reverse circulation drilling in thicker sediments adjacent to the eastern margin. Results indicated up to 12.6 metres of coarse sand and gravel occur above the basement contact and are restricted to a zone, up to 1.5 km wide and about 2.5 km long, adjacent to the Kitchener Fault. There is an upwards fining of sediments from the bottom unit which contains some pale grey, plastic clay lenses, through fine sand, silt and sandy clay, similar to Golden Grove. Although substantial reserves of construction sand exist, overburden ratios are too high for economic mining. Large reserves of finer, filling sand occur in the northern portion of the area investigated. Twenty samples were tested for gold to test basal Tertiary gravel and weathered basement. Only 1 sample was at detection limit of 0.02 ppm.