White Rocks Beach on Antrim's north-facing coast is named after the chalk that comprises the majority of the cliffs. Several interesting formations, such as the Wishing Arch, have been carved into the chalk by waves that have sought weaknesses where joints occur in the rock. The black pebbles on the shore are basalt from a volcanic eruption that caps the underlying beds, an event which was responsible for baking the normally crumbly chalk into a much harder form.