The Rex showing is located on the west bank of the Kitsault River, 21.0 kilometres north of Alice Arm. A quartz vein was explored in 1924 for precious metals in this area.

The region is underlain by an assemblage of volcanics and sediments comprising the Upper Triassic Stuhini Group and the Lower Jurassic Hazelton Group. These are folded into a doubly plunging north-northwest trending syncline and have been regionally metamorphosed to greenschist facies.

The showing consists of a quartz vein, up to 1.0 metre wide, striking 120 degrees and dipping 50 degrees southwest. The vein, hosted in Hazelton Group massive volcanic rocks, contains soft, grey sericitic inclusions impregnated with fine pyrite. A grab sample assayed 2.65 grams per tonne gold and 20.6 grams per tonne silver (Minister of Mines Annual Report 1924, page 53).

During 2010 through 2019, Dolly Silver Corporation explored the area as apart of the Dolly Varden property. A complete property exploration history can be found at the Dolly Varden (MINFILE 103P 188) occurrence.