A large number of Bullocks and descendants of the Bullocks worked in the China Clay quarries between St Enoder and St Austell in the latter part of the 19th century. The 1871 census reveals many of the family engaged in the industry. In general the work was back-breaking and poorly paid, but John Bullock of Bennalack Cottage near Summercourt, (a great grandson of John Bullock of 'Havenna Down Park') a 'Tin and Clay Agent' in 1871 was probably reasonably prosperous. His sons 22 year-old William and 17 year-old John, who were living at home, were working as tin miners, while 14 year-old Joseph was a 'scholar'. The immediate family of his distant cousin, another John Bullock (b. 1817), (great grandson of Edmund Bullock of 'Higher Hallone') who lived for the latter part of his life at Ruthvoes in St Columb Major parish were predominantly employed in the clay works. John himself, who was a maltster at the time of his marriage in 1839, was a 'tin mine captain' in the 1850's and in 1871 he farmed 35 acres as well as working as a clay labourer. His daughter Elizabeth  married a lay labourer named John Kessell and three of his sons, John, William and Albert were clay labourers. William rose to be the 'captain' of a china clay works.