Activity focused on the Coetia Ball cross-course, with shafts and mounds extending southwards from the Holywell Road. A line of shafts can be traced starting to the west of Brynderwen (SJ 1780 7622) and continuing southwards to Smithy Gate.

The placename “Ball” is thought to refer to early smelting sites, or “boles”.

Documented by Burt et al. (1992), with mining returns for the period of 1856-1859. After this, there was a phase of small-scale private speculation until the sett was taken over by the St Winifred Company between 1889 and 1890.