Lost River starts at an elevation of 1400 feet (427 m) on the south flank of the York Mountains on the Seward Peninsula and flows south for 9.5 miles (15 km) to the Bering Sea, about 86 miles (138 km) northwest of Nome and 31 miles (50 km) southeast of Wales, Alaska. The river has two main tributaries named Tin Creek and Cassiterite Creek. The latter is named for the mineral cassiterite which is the main source of tin. The York Mountains were named after Cape York which in turn was named by Captain Frederick W. Beechey in 1827 in honor of the Duke of York. The Seward Peninsula is a remnant of the Bering land bridge, a swath of land roughly 1,000 miles (1,600 km) wide that connected Siberia with mainland Alaska during the Pleistocene ice age. This land bridge facilitated the migration of humans, as well as plants and other animals, from Asia to North America. The peninsula is called ‘Kauwerak‘ by the Iñupiat people who inhabited this area and historically lived in seasonal villages in pursuit of subsistence foods. They also traded with people from Siberia, the Diomede Islands, and King Island.  In 1898, the peninsula was named after William H. Seward who negotiated the Alaska Purchase from Russia in 1867.

In 1898, a party of gold prospectors was returning from Kotzebue Sound on a schooner when they shipwrecked a few miles east of the mouth of Lost River. They built a cabin from the wreckage and spent the winter. These prospectors probably first applied the name Lost River to this stream. In 1899, the survivors organized a mining district that included the Lost River; however, no discoveries of gold were made and the region was abandoned. In the winter of 1902, prospectors again turned their attention to this region in the search for tin ore. In 1903, Charles Randt, Leslie Crim, and W.J. O’Brien found tin-bearing minerals in float or in panning concentrate from the Lost River. Assisted by Arthur J. Collier and Frank L. Hess of the U.S. Geological Survey, they traced the tin to its source in a rhyolite dike on the banks of Cassiterite Creek. This dike is now known as the ‘Cassiterite dike’ or the ‘Cassiterite lode’, and for several decades the Lost River Mine was the source of nearly all lode-tin production from the Seward Peninsula.

Tin-bearing mineralization has subsequently been found on the western Seward Peninsula associated with granitic intrusions and magmatic dikes exposed at Cape and Brooks Mountains, Tin Creek, and Black and Ear Mountains. Tin mineralization is present at all but Black Mountain. Since 1904, various mining interests intermittently developed the prospects in the area, and lode ore production totaled about 315 tons of tin-tungsten-fluorite by the 1950s. In 1983, the Lost River Alaska Corporation did some trenching, sampling, and mapping on the property. They built a support camp and a runway at the mouth of Lost River that was 3,650 feet (1,113 m) by 100 feet (30 m). More than 400 tons of tin was produced from the lode sources and inferred reserves were estimated at 38 million tons of ore based on 45,000 feet (13,720 m) of exploratory drilling. But plans for a townsite and a large mining operation never materialized due to financial problems, complexities of ore treatment, and lack of a market and transportation. In 2022, a newly formed company called Lost River Mining, Inc. began exploring for tin and other minerals from the mountains. Read more here and here. Explore more of Lost River and the York Mountains here: