300 million year old sandstone

"Numerous areas in Nova Scotia are underlain by Carboniferous strata. These strata are the province's source of coal, oil shale, salt, limestone, dolomite, celestite, barite, gypsum and anhydrite.

The Windsor Group consists of marine sediments. These include sandstone, shale, conglomerate, limestone, dolomite, gypsum, anhydrite and salt. Above the basal limestone, most of the limestones are very fossiliferous. It is within the Windsor Group that the majority of industrial minerals are mined. Total thickness of the Windsor Group varies from 1,000 feet to 10,000 feet."

- Geology Minerals and Mining in Nova Scotia

August 2006, near Walton, Nova Scotia