Possibly the site of the Westermin tinworks; "by the Cross of St Siward"
(Nun's Cross), this group of workings were known as Whiteworks (Wheal Whiddon in Cornish) prior to 1808, then tried under the title of Wheal Industry ("Wheal" is Cornish for "work/workings") 1848-1852. The last returns of tin date from 1876, amounting to 96tons.
Data courtesy of Ben Sum, Helston (1/7/18).
DRO = Devon Archives, South West Heritage Trust ("Devon Records Office")
Jenkins, A K H, 1974 "Mines of Devon: Southern District" Vol.1, David & Charles, Newton Abbot
[DRO] Lydford, Brooke Index