OAN field survey, located by GPS to an accuracy of +/- 1m. Large mine shaft located on a level plateau between the two water courses (with the Aber Sychnant to the west). The shaft is located to the north west of the Gweter Siani, lead vein, (NMR - 150346) and because of the alignment of the vein is most probably an outlier for that lead mining complex on the current OS mapping. The shaft is sub-circular and approximately 25m-30m in diameter with sloping sides that drop to a depth of 10m to point of blocking. bracken taking root to the western side. 2002/10/10/OAN/NW
