The remains of one of the finest surviving Arsenic-refining works in Britain with remarkable extant flues and a large double bayed labyrinth. An arch carrying the flue passes between the two main sections.
Tin produced in Cornish mines frequently contained arsenic and sulphur. These elements were detrimental to smelted tin and therefore had to be removed by roasting - this was done in burning houses or calciners , the vapour given off condensed on the walls of long stone tunnels called labyrinths. The miners then scraped the deposits of the chamber walls.
Location: SW 3642.3322