 The tin ore is intermixed with shorl and quartz and is quarried rather than mined, with the whole rock crushed and washed to separate the tin.The mine was worked exclusively for tin until 1851 when china clay was also quarried.Following the collapse of the price of tin in the 1860s, Carclaze continued to produce china clay and in 1873 the circumference of the pit was over , deep and covered about .