Salt is at the present time the most important of the non-metallic mineral products of the State, and has the distinction of having been the first recorded mineral exported from the region now known as South Australia. Salt has been gathered on a small scale for strictly local requirements for many years, but it was not until 1891, when 7,505 tons were produced, that the tonnage became notable. Owing to the low annual rainfall and consequent lack of run off, the high evaporation, and the presence of numerous basins of internal drainage, salt is very widely distributed in South Australia, and its occurrence is not confined to any particular geological horizon, unless the underlying rocks are totally disregarded and the salt deposits of the lakes are themselves regarded as recent.