The Manderfield showing is located near the eastern margin of the Stikinia Terrane 305 metres north of the Pollyanna deposit (093B 006).
The dominant rock types in the region are metabasalt, limestone and argillaceous metasediments of the Mississippian to Triassic Cache Creek Group. These are intruded by the dioritic to quartz dioritic Granite Mountain Pluton and the (?)Cretaceous Sheridan Creek Pluton.
The Manderfield showing consists of a six metre wide quartz vein on the west side of a 15 metre wide shear within quartz diorite. Secondary copper minerals coated the vein which contained chalco- pyrite. It appears that the location of this vein is now within the Pollyana pit of the Gibraltar Mine.