The preparation affords skill and a lot of time and experience. Using scrapers, skalpels and air-abrasive devices for fine sand guarantee best results. Traditional preparation-methods by means of steel and brass brushes are not adviseable: they destroy the delicate structures of the fossils.

In the Hunsrück Slate sediment layers and the cleavage of the rocks are normally not identical, but often are in a position at a certain angle, which leads to the fact that most fossils break when the slate is being split for roof purposes. Therefore almost all fossils have to be glued.

The fossils are either totally pyritized ore silicated or even covered with a thin layer of pyrite.
The differences in colour, ranging from black to a dark brass, are of natural origin.