Estimated Grid Ref. Later part of Gorland. operated during the 1790s as part of the northern section of Wheal Gorland under a separate grant. Because it was connected to the County Adit at a depth of around 50 fathoms below the surface, the mine didn’t require its own engine. Despite its small size, it managed to sell £1249 worth of copper ore between 1795 and 1798. Although the main mineral produced was tin, Wheal Muttrall eventually merged with Wheal Gorland and was developed to a depth of 126 fathoms on an inclined plane. The grid reference provided approximately marks the location of Muttrall’s Shaft. Dale Foster.