mine was considered to be of the highest quality. The Upper Coal Measures above the Worsley Four Foot mine, known as the Parker mine, are worked in this part of the coalfield and known as the Bradford Group, above which is the Ardwick Group. The coal seams of the Bradford Group are the Two Foot, Doctor, New, Yard, Bradford Foor Foot, Three Quarters and Charlotte mines, the Charlotte being closest to the surface. The Openshaw mine above the Charlotte was worked for fireclay. Below the Bradford Group and the Parker mine are the Top, Middle and Deep mines and below them, the Roger mine. The Top, Middle and Deep mines correspond to the Major, Bland and Ashton Great mines in the Oldham Coalfield. The Crumbouke mine in the western coalfield is the Roger mine in central Manchester. See also List of collieries in Astley and Tyldesley References Citations Bibliography Coal mining regions in England Geology of England History of Greater Manchester