In fact, there is no continent and hardly any country where ammonites have not been found. The prerequisite is precise knowledge of the formation conditions of the rocks in the respective subsoil. Naturally, no fossils can be found in igneous rocks from the depths of the earth or in solidified lava from volcanoes. Only the so-called sedimentary rocks potentially contain ammonites.

But even here, a find is not certain: firstly, the rock must have been deposited in the sea – because that is the only place where ammonites have lived – and secondly, the physical and chemical conditions in the mud of the seabed, into which the animals’ shells have sunk, must have allowed them to be preserved for millions of years.

Another prerequisite for a successful search is that the subsurface rocks are not covered by soil and vegetation. In our latitudes, we therefore generally have to rely on quarries, excavation pits or natural outcrops such as deeply incised streams. Cliffs, e.g. in England or northern France, also offer excellent conditions for a successful search.