Cassiterite

Unknown Owner

Lustrous crystals of cassiterite measuring to 0.3 cm in size on matrix. In good condition. The term sett refers to a defined mining claim or lease area, and Poldory Sett worked hydrothermal veins hosted in granite and surrounding metamorphic rocks typical of the Cornish mining districts. Cassiterite, the principal ore of tin, occurred in quartz rich lodes and was extracted by underground methods during the 18th and 19th centuries when Cornwall was a major world source of tin. Although many of these smaller workings are now abandoned, they are remembered for their role in the long tradition of Cornish tin mining and for mineral specimens recovered from the veins.