It is essentially flat-lying, with little or no soil cover, and its thickness averages 19 m. Relief is minor, with maximum elevations rarely exceeding 15 m above sea level. The ore body is of recent age, and the phosphate occurs as fine, rounded, granular sand, usually in the coarser fraction of the deposit. Minor amounts of magnetite, ferromagnesium, rutile, and sphene, as well as other miners, are present. Clay minerals are usually absent, except very close to the surface.
Color varies considerably but is usually yellowish to dark brown.
The resource is estimated to total 1.1 billion mt of rock. Detailed studies have been made for two mining areas, the Elenas and the Prados, using Longyear drilling equipment for sampling. Its southern limit lies just north of the fishing port of Lopez Mateos. The Prados zone is contiguous with the northern limit of the Elenas zone and is 9 km north-south. The western limit of the ore is an estuary formed by the barrier island, Isla Magdalena.