Columbus Colonists' Despair Revealed

Feb. 23, 2007 — The first silver ever extracted from coarser materials by Europeans in the New World appears to have been a desperate, last ditch effort involving not American, but Spanish metals, say archeologists.

The strange tale, entwined with Christopher Columbus’ questionable approach to attracting European investors to back his expeditions, has been uncovered at the site of the abandoned colony of La Isabela, on Hispaniola in the Caribbean.

The mystery started with the discovery of a leaden slag heap high in the layers of debris — indicating that it was one of the last things the colonists created before leaving what was the first European town in the Americas in 1498.

"We worked it out that it was for silver extraction," said archeologist David Killick of the University of Arizona in Tucson. The lead had been smelted in order to extract any silver it contained.

"We said, ‘This is interesting’," and they looked about the Caribbean to find out where the lead ore might have come from. They also collaborated with laboratory scientists who were able to identify the source of the lead by its isotopic signature.

"We discovered to our surprise that it was not from the Caribbean but from Spain," Killick told Discovery News. "That was a real head-scratcher."

Why in the world would Columbus’ colonists be carrying silver-bearing lead from Spain to the New World? Even more mysterious is why were they trying to extract silver from the Spanish lead?

The answer to the first question was easy for a metallurgist to explain. Melted lead was once used to extract silver and gold from crushed rock — similar to how mercury was used centuries later to dissolve and capture gold from ore, Killick explained.

So it made sense to bring some lead along from Spain for that purpose — since gold and silver were what Columbus promised his royal sponsors.

The trouble was, the only precious metals Columbus had found around La Isabela, which was settled in 1492, were jewelry stolen from local inhabitants, said Killick. That was used to convince investors to back his expeditions.

"Columbus led them all on," Killick said. But not for long. In 1496 Columbus was shipped back to Spain in chains and his colonies were left to fend for themselves.

"From the archaeology it looks like the smelting (of the silver from the lead) was the very last thing to be done on the site," said Killick. "We know that this lead is royal supplies" because they match the lead isotope signatures. They were also smelted right beside the royal storehouse.

"You would never put a smelter there," agrees Southwest metals researcher Ann Ramenofsky of the University of New Mexico in Albuquerque. "It is such a messy process."

It appears that the abandoned colonists rebelled, broke into the royal storehouse and smelted about 450 pounds (200 kg) of lead in hopes they’d get a worthwhile amount of silver out of it.

"There was a pathetically small amount of silver in the lead," Killick said. So little they gave up and left another 450 pounds of lead un-smelted. Then they left La Isabela for the mountains and took up banditry.

Ramenofsky agrees with Killick’s interpretation.

"As we know, the colonists didn’t have a lot of resources," said Ramenofsky.

A paper describing the La Isabela discovery by Killick, Alyson Thibodeau, Kathleen Deagan and their colleagues appears in the Feb. 27 issue of the Proceedings of the National Academy of Science.