The Hollinside and Riding Field coal estates were owned by the Harding family. The Hardings were non-freemen, barred from the Hostmen's Company. They could work coal but could not sell it. The Hardings shared boundaries with coal-hungry entrepreneurs and so their Riding Field became a virtual extension of the Whickham Grand Lease. By 1606 Grand Lessees had acquired part of the easily accessible hilltop coal and had two pits extracting about 200T a year. By 1617 the Whickham Grand Lease Colliery was a vast adventurous project. In 1623 half of the Riding Field was granted to John Clavering, at a rent which suggests an output of 500T. By 1625 the Harding estate had become a major colliery but was out of their hands. At Riding Field the coal was easily won, transport was the main cost. In 1629 John Clavering added to his Riding Field lease with a share of the Hardins' Hollinside coal. He was in partnership with Henry Maddison, greatest coalowner of the time. The whole area was drained by an adit in Clockburn Lane by the 1630s. Whickham's resouces was producing over 1000T. Throughout the 17th century coal on the Harding estates continued to be exploited by leading Hostmen partnerships. By 1692 the aged Sir James Clavering gave way to a partnership of the heirs of his Puritan circle, who had given Hollinside a waggonway (the Riding Field).