A sole reference survives for this mine on a plan of Birch Tor & Vitrifer Consols (working 1859-86) in the Cornwall Archives. It is tempting to speculate that this name might relate to the extensive use of water in medieval eluvial tin works here, but for now this is apocryphal.
Data courtesy of Ben Sum, Helston (30/9/20).
[CRO] = Cornwall Archives, Kresen Kernow, Redruth
References:
[CRO] Plan, Birch Tor & Vitrifer Consols, c1859-86