Geology

Purbeck Stone is a hard sedimentary limestone. We quarry from two different geological horizons: the Purbeck Portland beds and Purbeck Inland beds. 

The Purbeck Portland beds are Jurassic, and were deposited at the same time as those found on the Isle of Portland in west Dorset. The Purbeck Portland beds are marine deposits, laid down about 150 million years ago in a warm, shallow, high-energy sea similar to conditions found in the Bahamas today. We commonly find fossils of the huge ammonite Titanites that swam in these waters. 

The Purbeck Inland beds are found above the Purbeck Portland, and are Cretaceous. In contrast, these were deposited in a brackish lagoon. This is why we find such an abundance of both aquatic and terrestrial fossils in these stones, including fish, alligator teeth, turtles, shells, fossil wood, and dinosaur footprints. 

Aside from these occasional fossils, Purbeck Stone is densely packed with innumerable small shells that can be seen clearly when the stone is cut and polished. This evidence of prehistoric life gives the stone its rich visual character.