Silvermine is one of three mines still in tact in the Greater Cape Town region. It comprises a shaft 16 metres deep and 4 by 3 metres in areal extent that was excavated in 1687. No silver ore found but narrow bands of manganese ore, dark blue-black in colour were possibly mistaken for silver ore. Reference: Spargo (2010).The early mines of the Cape Peninsula. Kalk Bay Historical Association, Bulletin No. 14, pp. 1-37.