Great oolite

Great Oolite or the famous Bath Stone. It is used as a building stone in the well-to-do Georgian buildings in Bath. It is still quaried in the area today and is mostly used for restoration. Most of the quaries are underground, stone mines.

It is an oolitic limestone that formed in warm shallow seas similar to that forming offshore of the Bahamas today. The rock is made up of ooids and shelly fragments held together by calcite. Ooids are formed in turbulent water, where there is high evaporation. A small shelly fragment is rolled around on the sea floor and concentric layers of calcium carbonate precipitate around it.

Reference Bath In Stone by Elizabeth Devon, John Parkins, David Workman and The Rocks Of Brown's Folly by Ron Smith