The Brynford Hall sett exploited the Milwr Vein, which ran east to west, passing north of Brynford Hall. The primary working area appears to have been west of the Hall, where a significant waste area remains.Evidence of extensive earthworks and mining subsidence can still be seen on both sides of Brynford Road as it ascends from the former workhouse, now Lluesty Hospital.
Additional shafts extend east to west in the fields south of the Hall and west of the modern Pystyll housing estate. These southern parallel veins, known as the Ellis and Beili-gwyn Veins, were also worked extensively. A day-level was driven beneath the Halkyn-Holywell Road to assist with drainage, and water continues to emerge from a point at SJ 1923 7470.
The Brynford Hall Mining Company operated until 1870, after which the mine was incorporated into the Milwr Group and later the Herward Mines.
