The Fort Drum Crystal Mine, Florida, USA

The Pliocene and Pleistocene deposits of South Florida contain a spectacularly rich fossil record and chronicle several cycles of marine inundation and freshwater lake formation. The Pinecrest, Tamiami, Caloosahatchee and Bermont formations are famed for the variety and preservation of their molluscan faunas. It is therefore sad that good exposures are ephemeral and where they do exist it is very difficult to gain access. In addition, the large commercial pits that exploit the sediments for landfill and aggregate are rarely pumped dry, the material being extracted by draglines from the flooded pit, thereby rendering it impossible to study the stratigraphy.