The smaller Margaret Island is 1 km (0.62 mi) to the east of Dundas.

Dundas Island is named in honour of Henry Dundas, 1st Viscount Melville, Viscount Melville and British Secretary of State for the Home Department.

After showings were discovered on Dundas Island in 1972, geochemical sampling, mapping, and surveying began the following year.

Canadian mining company Cominco (now part of Teck Resources) staked claims in 1974 and drilling occurred at high grade lead-zinc showings at the Thumb Mountain Formation and Disappointment Bay Formation in 1975.

[1][2] Robert John McGhee's 1981 research found evidence of Late Dorset warm-season dwellings on Dundas Island.