Cassiterite

Unknown Owner

Lustrous black crystals of cassiterite measuring to 0.3 cm in size across the top of matrix. In good condition. Poldory Sett at United Downs near St Day in Cornwall, England, was a historic mining sett within the larger United Mines group that worked copper and tin lodes in the Gwennap mining district from the late 1700s into the 1800s. The name Poldory (also spelled Poldory or Poldory Sett) refers to one of the mineral lease areas around United Downs where cassiterite (tin ore) and other minerals were extracted as part of the extensive Cornish metalliferous mining operations of that era.