 The 2,500- to 2,450-million-year-old Matachewan dike swarm of eastern Ontario hosts the 2,491- to 2,475-million-year-old long East Bull Lake Intrusion and associated intrusions.The 2,217- to 2,210-million-year-old Ungava magmatic event was the source for the Nipissing sills of Ontario and have been historically important for copper, silver, and arsenic mineralization, and also have the potential to contain platinum group metals.A third major event is the 1,885‑ to 1,865‑million-year-old magmatism of the Circum-Superior Belt surrounding much of the Superior craton from the Labrador Trough in Labrador and northeastern Quebec, though the Cape Smith Belt in northern Quebec, the Belcher Islands in southern Nunavut, the Fox River and Thompson belts in northern Manitoba, the Winnipegosis komatiite belt in central Manitoba, and on the southern side of the Superior craton in the Animikie Basin of northwestern Ontario.