One of the notable mines in the Nenthead area, it wasn’t developed by the London Lead Co., unlike many others. It was established from two levels: the Bloomsberry Horse Level, now referred to as Brownley Hill Low Level, and Brownley Hill High Level. The veins mined included Carrs Vein, Wellgill Cross Vein, Brownley Hill Moss Cross Vein, West High Cross Vein, High Cross Vein, and Jug Vein, which predominantly ran north to south. Additionally, there were east-west veins such as Brownley Hill North Vein, Brownley Hill Vein, Tatters String Vein, North Middle Vein, Middle Vein, and Sun Vein. Replacement orebodies, or flats, were situated east of Wellgill vein, associated with Middle Vein. There was also a small replacement area between Brownley Hill and Brownley Hill North Veins, possibly linked to Tatters String. Alstonite was extracted from the High Cross Vein. When high-grade lead ore became scarce, the Vieille Montagne Zinc Company took over the lease in 1914, shifting focus to zinc ore extraction. The mine operated under VM from 1914 to 1936. While extensive sections of the mine can still be accessed from the Low Level, the access levels are mostly in poor and hazardous condition, despite the Great Limestone workings being relatively well-preserved.