The Benson showing occupies the entire area of Benson Island (previously known as Hawkins Island) located within the Broken Group Islands in Barclay Sound.

The area is underlain by the Paleozoic and/or Mesozoic Westcoast Complex comprising diorites, metavolcanic and metasedimentary rocks including lenses of recrystallized limestone and skarn. These are intruded by granitic rocks of the Early to Middle Jurassic Island Plutonic Suite.

On Benson Island, these limestone and skarn lenses are hosted in a rock resembling granodiorite. Mineralization, apparently of limited extent, consists of magnetite.

A sample from one of the magnetite outcrops assayed 44.5 per cent iron (Annual Report 1918 p. 260). No other information is available.