MINING IN CALSTOCK PARISH
There is little evidence in the parish of early tin-streaming, the working of alluvial deposits, but it must have taken place. At a later date, outcrops of tin-bearing rock would have been worked and there are examples of lode- back pits, narrow openworks and early shafts to be seen at Clitters Wood, probably dating from the eighteenth century. One mine sett which saw all stages of tin production, with records of tin-streaming dating from mediaeval times, through openworks of the sixteenth century, down to true mining in the later eighteenth and nineteenth centuries, was Drakewalls mine at the top of Gunnislake Hill; some of the surface remains have been stabilised, with improved public access. Many of the mines in the parish produced some tin and worked actively into the twentieth century; some were examined and/or reworked in the Second World War and there was a flurry of prospecting activity in the early 1970s. Prince of Wales Mine at Harrowbarrow is still regarded as 'one of the best prospects in East Cornwall' should the price of tin rise.
Prince of Wales Mine
The most productive period of mining in the parish began in the late eighteenth century when John Williams of Scorrier developed the Gunnislake Sett for copper. The major copper producer for the parish was the Hingston Down Consols with 64,440 tons of ore recorded for the period 1850-1882; little remains to be seen on surface - the engine house at Bailey's Shaft dates from an early and short-lived twentieth century re-working.
Surface remains at two other major copper producers, Gunnislake Clitters and Okel Tor, have also been consolidated and had access improved. Following the opening of Devon Great Consols in 1844, on the Devon Bank, several small mines were promoted around Chilsworthy and Latchley in the hope of picking up the western extensions of the lodes; copper was found but none of these mines lived up to expectations.
Surface remains at two other major copper producers, Gunnislake Clitters and Okel Tor, have also been consolidated and had access improved. Following the opening of Devon Great Consols in 1844, on the Devon Bank, several small mines were promoted around Chilsworthy and Latchley in the hope of picking up the western extensions of the lodes; copper was found but none of these mines lived up to expectations.
Coombe Arsenic Works
The Cinderella of the Tamar Valley mining activity is the production of arsenic. Arsenides and sulphides containing tin ore were initially burned off to atmosphere but in the early nineteenth century several uses were found for refined arsenic. From the 1860s, purpose built recovery units were constructed. One mine in the parish with a fully developed arsenic recovery plant was Okel Tor, but there were two large plants at Greenhill above Gunnislake and at Coombe in Harrowbarrow, which did not mine their own ore but brought in untreated arsenic ore or arsenic soot to be refined.
Although the principal silver/lead mines in the valley are in Bere Ferrers parish, a group of small mines west of Harrowbarrow were developed on silver/lead lodes, among them Wheal Brothers where a public footpath gives access to the surface remains.
The demand for tungsten prior to and during both World Wars led to both mining and reworking of dumps. Dumps were reworked at Hingston Down Consols and at Gunnislake Clitters, where a large mill for treating both tin and wolfram was opened in 1900 and closed in the late 1920s, substantial remains of which may still be seen.
The demand for tungsten prior to and during both World Wars led to both mining and reworking of dumps. Dumps were reworked at Hingston Down Consols and at Gunnislake Clitters, where a large mill for treating both tin and wolfram was opened in 1900 and closed in the late 1920s, substantial remains of which may still be seen.
