Among the most evocative of all the Gold Rush issues, the huge octagonal $50 gold pieces nicknamed "slugs" have been favorites of numismatists for generations. Tokens and medals made in imitation of the iconic pieces have been produced throughout the twentieth century and even the ever-popular Panama-Pacific Exposition octagonal $50 commemoratives were based loosely on the slugs of the United States Assay Office of Gold.

Humbert's $50 "slugs" are often seen with heavy nicks and edge bruises, as the soft metal would not withstand the hard use that it saw. It was commonplace to toss them into bags of gold in various forms, including bars, for transportation. Those surviving examples that do not show these imperfections have often been repaired in an attempt to "improve" their look over the years.

The example to the left was sold by Stack's Bowers Galleries in November 2019 Baltimore Auction, where it realized $120,000.