The most significant finds historically at the SS Central America wreck were probably the hundreds of gold ingots cast by private assayers in California. Until the Central America discoveries, original California Gold Rush ingots were virtually unknown. Almost all had been melted and turned into coins after being shipped from the gold fields to the East.
Five firms were represented among the nearly 500 ingots found at the wreck site during the 20th century salvage — Blake and Company (34 ingots found), Kellogg & Humbert (343 ingots recovered), Justh and Hunter (85 ingots found), Harris, Marchand & Company (37 ingots found), and Henry Hentsch (33 ingots found).
All of the firms were known previously, but the discovery of so many ingots helped researchers like Bob Evans and Q. David Bowers understand the issuers and their practices better.
As reported in the Aug. 7, 2000, issue of Coin World, in an article by Paul Gilkes, “Evans said regardless of the size or shape of the bars, each is stamped with the same five pieces of information, albeit not in the same location: the name and/or identifying stamps of the manufacturer, the serial number, the weight in fine troy ounces, the purity in parts per thousand, and the dollar value based at $20.67 per ounce of pure gold. The treasure bars range in fineness from .580 fine to .973 fine.”
Gilkes wrote, “The unparted bars ... were produced in molds from unrefined gold dust melted in crucibles and then poured into the molds. No attempt was made by the assayers to change the purity of the gold in the bars. ...
“The deeper the golden color of the bar, the higher the gold fineness, Evans said. The lower the fineness, the lighter yellow the appearance," according to Gilkes.
The largest bar found at the wreck has been dubbed the “Eureka” bar — an 80-pound slab of gold cast by Kellogg & Humbert.
The bars found at the wreck site have long been dispersed into the marketplace at impressive prices (the Eureka bar sold for approximately $8 million).
The saga of the SS Central America is far from over. The discovery April 15, 2014, of more gold at the wreck site, and the belief by some researchers that the ship’s hold carried a secret U.S. Army shipment of gold totaling 3 tons, will keep this story going for years.