Silver Islet refers to both a small rocky island and a small community located at the tip of the Sibley Peninsula in northwestern Ontario, Canada. A rich vein of pure silver was discovered on this small island in 1868 by the . At that time, the island was approximately [50 m²] in size and only 2.5 metres above the waters of Lake Superior. In 1870, the site was developed by Alexander H. Sibley's Silver Islet Mining Company which built wooden breakwaters around the island to hold back the lake's waves and increased the island's area substantially with crushed rock. The islet was expanded to over 10 times its original size and a small mining town was built up on the shore nearby.