Modern exploration at the north end of Vancouver Island began in the mid-1960s with the release by the Geological Survey of Canada of an airborne magnetic survey. Initial exploration by companies and individuals focused on the search for iron ore deposits with exploration targeting magnetic high anomalies identified by the airborne survey.

In 1966, Dennis Milburn, a prospector, discovered copper mineralization at the eastern end of Rupert Inlet. The property was subsequently option by Utah Construction and Mining, who drilled out the deposit between 1966 and 1969. At the western area of what is now the NorthIsle claim block, Hans Veerman and William Botel discovered the Red Dog prospect in the mid-1960s. In 1967, Utah staked claims along the north shore of Rupert and Holberg Inlets including the ground surrounding the Red Dog Property. Exploration of this large package of claims, referred to as the Expo Claims, led to the discovery of the Hushamu deposit in the late 1960s. Up to 1980, Utah’s exploration was aimed at discovering additional porphyry copper mineralization and the drilling of the Hushamu deposit. In 1980, Utah shifted its focus to the search for gold. This work resulted in discovering the Pemberton Hills occurrence.

In 1987, Moraga Resources Ltd. optioned the Expo property from Utah. From 1987 to 1994 Moraga carried out extensive drilling and scoping studies of the Hushamu deposit. From 2003 to 2008 successively, Lumina, Western Copper and IMA Exploration carried out airborne geophysical surveys and drilling of the NW Expo zone as well as some drilling on the Hushamu deposit.

The Red Dog project was initially explored in the late 1960s and 1970s by a number of companies. Early drilling centred on the Slide Zone. With the discovery of better mineralized breccias, drilling shifted in the early 1980s to the Red Dog Knoll. The Red Dog Knoll was drilled by Utah in the early 1980s and by Crew Resources and Moraga Resources in the late 1980s and early 1990s. Up until the recent drill program of Northisle, no drilling had been done on the Red Dog Property since 1991.