The majority of the Triassic Sandstones found in Worcestershire are from the fluvially deposited Sherwood Sandstone Group (named after its type outcrop in Nottinghamshire) which outcrops across the centre and north of the county. The group consists of red, brown and grey sandstones, commonly pebbly or conglomeratic at the bases of beds, interbedded with red and brown siltstones and mudstones.
From oldest to youngest; the Sherwood Sandstone is made up of the Kidderminster Formation (previously known as the Bunter Pebble Beds), Wildmoor Sandstone Formation (Upper Mottled Sandstone) and the Bromsgrove Sandstone Formation (Lower Keuper Sandstone). Of these the Bromsgrove Sandstone Formation is the most widely used for building stone while the Kidderminster Formation has mainly been exploited for sand and gravel and the Wildmoor Sandstone’s softness makes it as suitable for cave digging as it isn’t for building.
Overlying the group is the Mercia Mudstone Group which has generally been used only for clay with the exception of the Arden Sandstone Formation which is an important stone in some areas.