More correctly "Long Roost", as it would have been spelt in the time of the Rev. William Hudson Heaven; this "mine" consists of 3 adit trials driven in from above the high water mark and mid way up the cliff. None of the tunnels extend more than 40ft and under assay, the copper veins prove to be very poor.
The group of workings were surveyed 1967-9 by the Lundy Field Society and are described in their publication of 1972. For more about the accession into ownership of the Heaven family, the Telegraph has published an informative read (NB: not even fake news!)
Data courtesy of Ben Sum, Helston (21/7/18).
www.goo.gl/ApMrwg ("Lundy: My family and the Kingdom of Heaven", Accessed 21/7/18)
M T Mills, 'The Copper Mines of Lundy', 23rd Annual Report, Lundy Field Society, (1972)
Schmitz, C "The Granite Quarries & Mineral Mines of Lundy", No.10, Jour. Bristol Ind. Arch. Soc. (1977)