Mount Compass is an important sand resource area. The ACI Glenshera sand pit, which supplies Australia's largest container glass plant at West Croydon with over 100 000 tonnes per year of glass sand, is also a major source of foundry sand. Four other pits produce a range of sands used mainly for garden and filling purposes. The Mount Compass deposits are fluvioglacial sands, of Permian age, in contrast to all the other major sand resources supplying Adelaide, which are of Tertiary age. A program of 64 reverse circulation holes totalling 2463 metres was drilled near the township of Mount Compass in late 1997, in areas where the water table was expected to be at least 20 m deep. The dominant lithology intersected was subrounded to rounded, fine to medium-grained fluvioglacial sand. Reworked Tertiary sand was intersected at the top of many holes. Permian fluvioglacial deposits in the Mount Compass area contain large resources of sand for garden, filling and packing purposes. Although this sand is suitable for making mortar mixes, it is generally too fine for use in concrete. The lack of a supply of coarse concrete sand in this area highlights the importance of the Extractive Industry Zone at Maslin Beach as the only major source of coarse construction sand south of the City of Adelaide. Sieve sizing analyses and preliminary beneficiation studies of the Mount Compass sands indicate that there is considerable potential locally to prove up additional deposits of glass sand. Five areas are nominated which warrant follow-up drilling and testing.