Butterley Company correspondence file on minerals of land at Lenton, leased by Mr. F. P. B. Osmaston's estate to the Clifton Colliery Company Also mentions Deep Hard seam at Lenton was subleased to the Butterley Colliery Company. Includes extracts of draft agreements. Plan of the Deep Soft Coal workings abandoned, early 20th cent, scale 1:2500, 30cm x 30cm, with duplicate copy. Apr 1920-Mar 1935