Swanberg Dredge is a historic placer mining machine, located in a small artificial pond at Rocker Gulch, that once extracted gold from sand and gravel on the Seward Peninsula, about 18 miles (29 km) west of Safety and 1 mile (1.6 km) east of Nome, Alaska. The dredge is approximately 200 feet (61 m) north of the Nome-Council Highway and is named after Nelson Swanberg Jr., a part owner of the Rocker Gulch claims before 1940 and the dredge’s owner in 1966. Rocker Gulch is an alluvium-filled depression, named for a rocker sluice box used in placer mining to separate gold from alluvial sand and gravel. Placer gold has been the main metallic mineral extracted from the Nome mining district. From 1898 to 1993, an estimated 4.8 million ounces (150 metric tonnes) of gold were extracted from beach deposits, with the remainder from streams, colluvial hillslopes, and glacial deposits. About 70 percent came from placer deposits along modern and ancestral beaches and nearshore areas of the Bering Sea, especially near Anvil Mountain and tributaries of the Nome, Osborn, and Snake rivers. Most of the area is covered by till or drift deposited during a series of Pleistocene glaciations. The most extensive surface drift occurred during the Nome River glaciation in the Middle Pleistocene. Ice from this advance flowed southward out of cirques in the Kigluaik Mountains, merging with local ice from cirques and small ice caps in the uplands north of Nome. The Nome River glaciation’s ice filled the major trunk streams near Nome and extended several miles (approximately 11 km) into what is now Norton Sound. Subsequent glacial advances reached only about 6 miles (10 km) from the Kigluaik Mountains. During and after these ice expansions, fluvial, colluvial, and marine processes modified the landscape, forming gravel-rich alluvial valley fills, beaches, and terrace sediments.

The western point of the Seward Peninsula is less than 60 miles (100 km) from the Siberian coast. In 1711, Peter I. Popof learned from the Chukchi people people about a great land with broad rivers and inhabitants beyond the islands off Siberia. The first landing occurred in 1732 when Ivan Fedorov and Mikhail Gvozdev, on the Saint Gabriel, crossed the Bering Strait, discovering the Diomede Islands and sailing east toward Cape Prince of Wales on the North American mainland. Captain James Cook made the first coastal survey in 1778. During the subsequent century of Russian occupation, the entire coastline was explored. In 1822, Russian Captain Vasiliy S. Khromchenko, commanding the Golovnin, surveyed Norton Sound and Golovnin Bay. A trading post was established on Saint Michael Island in 1835, the first Russian settlement north of the Aleutian Islands, facilitating trade with the Yup’ik people. In 1865-66, Ottfried von Bendeleben led a significant exploration of the interior while seeking a telegraph route, reportedly finding alluvial gold on the Niukluk River. After the Alaska Purchase in 1867, the peninsula was seen as barren. Whalers gathered at Port Clarence in early summer, waiting for sea ice to break up. Occasionally, traders from posts like Unalakleet or Saint Michael bartered with the Natives; otherwise, conditions remained primitive. Major alluvial placer gold deposits in the Nome mining district were discovered in September and October 1898 by John Brynteson, Jafet Lindeberg, and Erik O. Lindblom, supported by several Yup’ik Eskimos, including Gabriel Adams and Constantine Uparazuck. The men were part of a Scandinavian community based in Golovin, originally drawn to the region mainly for the Swedish Covenant Church. Many of the best placers were identified in 1898, and a mining district was formed. The following year, gold was found on the beach at Nome, leading the US Geological Survey to predict the discovery of buried beach placer deposits. Initially, the placers were exploited mainly by hydraulic methods, with major ditches constructed to supply water. In the 1920s, after the invention of cold-water thawing to melt permafrost, large dredges were introduced in the thaw fields by Wendell P. Hammon. His interests were later consolidated by the US Smelting, Refining, and Mining Company.

Gold mining languished during World War I but increased dramatically after President Franklin D. Roosevelt raised the price of gold from $27 to $35 an ounce in 1934. However, mining was restricted again in 1942, as it was deemed non-essential to the World War II effort. After the war, the Gold Beach Dredging Company acquired claims to Rocker Gulch, hoping to resume operations. In 1946, the company purchased a small gold dredge in San Francisco and shipped it in pieces to Nome, where it was reassembled by Walter Johnson. The dredge operated for only one season before a local bank owned by Grant Jackson took possession of it. The Gold Beach Dredging Company aimed to reclaim the dredge and, in 1948, acquired rights to dig a ditch from the Nome River to Rocker Gulch, although the ditch was never constructed. The dredge remained with the bank until the Alaska National Bank of Fairbanks bought it in 1963. In 1966, Alaska National Bank sold the dredge for an undisclosed sum to board member Nelson Swanberg Jr., who originally owned the Rocker Gulch claims before 1940. Swanberg used the dredge as a tourist attraction, and today the City of Nome owns it as part of Gold Rush Park. The dredge remains where it ceased operations and serves as an example of a small, remote mining operation. It illustrates the economic risks of gold mining and the challenges faced by miners working in the far north during the mid-20th century. The Swanberg Dredge features a barge-like steel hull, measuring 60 feet (18 m) long, 30 feet (9 m) wide, and about 6 feet (1.8 m) deep. A coal-fired boiler in the hull provided steam heat, and a diesel generator supplied electrical power for the machinery. A one-story superstructure covers almost the entire hull. The bow half of the superstructure includes a second story, housing the winch room, hopper, and upper end of the trommel screen. The superstructure is steel with corrugated metal sheathing, and the flat roofs are covered with metal sheets. Read more here and here. Explore more of Swanberg Dredge and Rocker Gulch here: