This is a rare & unusual rock, part of the highly studied Zechstein Formation. It is a concretionary Magnesium Limestone of Permian age, supplied in a 1.5″ x 1.5″ magnification box.
Small specimens of a very distinctive & rare limestone known as Cannonball rock. It is a concretionary Magnesium Limestone / dolostone which formed due to primary and secondary sedimentary processes; this material is specifically the carbonate concretions. It is part of the Rocker formation; a basin slope deposit which comprises part of the Zechstein Group; a highly studied sedimentary formation which was laid down in the epeiric Zechstein Sea during the Mid to Late Permian Period. This limestone is suitable for educational purposes, particularly carbonate and sedimentology modules but also just for those who are interested in geology. The material was collected around Hartlepool before it became a highly restricted site. Specimens of this rare limestone are only small and are supplied in a 1.5" x 1.5" magnification box.