Mulde Formation

The Mulde formation is a sequence of Silurian bluish-gray marlstone and agrillceous limestones found on the southwestern part of the island of Gotland. It generally becomes harder and less marly in the upper parts of the formation.
Fossil content.
The formation holds some of the best fossils on Gotland, being the best place to find well preserved trilobites. Some examples are "Calymene", "Dalmanites", "Encrinurus" and "Proteus". Ostracods (beyrichids etc.), brachiopods ("Atrypa reticularis", "Leptaena", "Eospirifer" etc.), bryozoans and tentaculitids are also relatively common while corals, grapolites, annelids and cephalopods are more rare.