Receiving no attention in publication to date, the 'Swiss Cheese' workings here - never worked beyond private speculation - are the most Northerly examples of tin mining to the observed on the North Coast of Cornwall.
The cartographic record of these workings are tantamount to an 1830s plan of tin bounds, and covers the district west of the assesstion properties of the Duchy manor of Tywarnhaile. The 'farmer' or 'bounder' at this time was a J W Barnicoat, an individual famous in the district for his extensive properties. Prior to this however, in the 1780s, these bounds were worked by Mr Cotty after whom the headland and common holds its name today. Cotty's bounds are recorded in correspondence between prominent manorial lords (such as the Enys') and other bounders (the likes of the Bolithos) and encompassed the majority of Cligga Head and Perranporth.
The earliest indication of tin mining in the district however is a reference to the "Perrant in the Sands" tin works, in 1597. While this most likely refers to alluvial tin streamed in the Ponsmere river, or outcrop workings of Wheal Ramoth, it is undoubtable that the cliff lodes of this striking headland were discovered by this time, even if it was deemed impractical to work them.
Penal-Due ("Pen Al Due") roughly translates to the "Black Cliff Head"; 'black' potentially referring to dark killas rock rising out of the surrounding sand dunes, or more likely the black cassiterite ore of tin.
Data courtesy of Ben Sum, Helston (12/5/18)
NB: CRO = Cornwall Records Office, Truro (Soon to be Kressen Kernow, Redruth)
PA = various manuscripts in private possession
[CRO] Mr Cotty's account, Bolitho papers
[PA] Series of maps detailing Barnicoat's tin bounds in St Agnes, Perranzabuloe & Kenwyn
[CRO] Transcription of Mines Royal correspondence, Rev Picken papers, Perranzabuloe