Situated within Carboniferous limestone with veins trending NNE-SSW. The mineralisation includes a calcite gangue with lead and copper ores, primarily in the form of secondary oxidation products such as cerussite and malachite.

The main workings are divided into several series: the Pit Series, the Winze Series, and the Ogof Llanymynech workings. The Winze Series, located at SJ 2650 2236, includes a long adit at SJ 2658 2225, leading to a winze and several levels. The Pit Series consists of two parallel levels continuing northwards, visible on the surface as a line of shallow pits at S J2647 2222, which appear to connect with the Winze Series workings.

The southern quarry face features three levels, one of which terminates abruptly, while the others continue north and link with three shafts in the Carreghwfa workings at SJ 2650 2186. A connecting quarry tunnel links the two main quarries.

Additional adits are found in the area, including one running west from the base of a quarry on the eastern side of the hill at SJ 2693 2219, though it does not continue far. Another adit is believed to appear in the western cliff face but can only be reached by ropelines, and its precise position is unconfirmed.

The remains of lead and copper processing can be inferred from the reported presence of bole hill smelters and processing spoil heaps, though much of this was destroyed during the construction of the golf course.

Lead and copper extraction took place from ancient times, continuing through the Roman era and later into the 19th century. Excavations by the CPAT in 1981 inside the eastern multivallate defences revealed metalworking hearths, which suggest the reworking of smelted local copper ores. These activities have been radiocarbon dated to the second and/or first centuries BC, indicating that the site was significant in antiquity for metal production.

Lead and copper processing is thought to have taken place on the hilltop, as evidenced by the former existence of bole hill smelters and processing spoil heaps, which were cleared for golf course landscaping.