An 1852 Assay Office $50 piece was the headline lot of Heritage Auctions' sale at the Houston Money Show on December 4-7, selling for $396,562.
The coin was issued by the United States Assay Office, which was founded in San Francisco in the absence of an official branch mint.
The present lot is among the finest examples extant (it's the only-MS64 graded specimen) and is believed to have been part of the collection of chief assayer Augustus Humbert.
Other lots in the sale included an 1870-CC double eagle that made $305,500.
The AU50-graded lot is one of just 35-45 surviving specimens of the first year Carson City issue. This is the first time this particular coin has appeared at auction in almost 30 years.
Heritage comments: "The strike is soft on all examples of the Carson City date, especially on the star centers, but the current coin is at least the equal of any other known representative of the issue.
"It would not be hard to imagine this example inching up the grading scale based on its overall quality and eye appeal compared to the other high-grade coins."
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