Carclaze Mine was in production for over 400 years, first for tin and copper, then china clay from the 1860's.
Tin deposits were found at Carclaze mine, which for centuries up till then had been returning a unspectacular, stream of tin. It soon became the largest open tin-mine in the world and eventually, the pit extended one mile across. After the price of tin collapsed, in the 1860's, Carclaze was found to contain huge quantities of china clay, one of the few mines to do so. Because china clay continued to be produced , miners throughout Cornwall moved to the area as other mines closed. China clay is still a valuable resource.
1873 Kellys Directory. Carclaze mine or works, about 2 miles north of the town, at an altitude of 665 feet. from the summit of this rising ground the mine is sunk to the depth of 150 feet, open, somewhat in the shape of an enormous bowl, the surface of which measures upwards of 12 acres, its circumference more than a mile: it is supposed to have been in working more than 400 years, and until 1851 for tin exclusively, but is now worked for china clay, of which an immense quantity is washed from the decomposed, granite which forms its strata. Managers John LOVERING & Robert Martin at the mine
The white pyramids of waste from the china clay tips make the St Austell area look like a tented city from a distance. Since the Aberfan disaster in 1966 all waste tips had to be contoured and grassed over to stabilise them. One of the exceptions was the tip from the Carclaze pit.
Mining in St Austell Area