Many mineral resource maps for areas of Great Britain at scales of 1:25 000 and 1:50 000 have been produced by the British Geological Survey and its predecessors. Many of these maps were produced by the Industrial Minerals Assessment Unit (IMAU) from 1971 to 1986. Most maps cover a single 10 km x 10 km grid square, but some cover larger areas. The majority of maps are sand and gravel resource maps, but conglomerate, limestone, dolomite and celestite are also covered in certain regions. The maps show the locations of IMAU mineral resource blocks, the locations and categories of resource deposits and the locations of boreholes with indicative logs. A series of technical reports (Mineral Assessment Reports, MARs) was also created alongside the maps. Refer to the metadata entry for the Mineral Assessment Reports for more information. The maps are intended to be used for resource development, strategic planning, land-use planning, the indication of hazard in mined areas, environment assessment and as a teaching aid. The data was originally published in printed map form. The printed maps have been scanned and added to the BGS Maps Database.