Worked within Ordovician Van grits, where the east-west striking vein contained galena and zinc mineralization.

Shaft located at SN 8542 8662 on the main mine site. Further downstream, two blocked levels at SN 8565 86670 and SN 8573 8678 suggest additional workings. However, these levels may be associated with the nearby Rhyd Y Bennwch workings rather than the Maesnant sett.