NEWS OF THE WEEK

COLUMBUS' SILVER MINING DEBUNKED

ARCHAEOLOGY: Chemistry rewrites history of precious-metal

processing in New World

CHEMICAL ANALYSIS of metallurgical artifacts from La Isabela—the settlement Christopher Columbus founded on his second trip to the

New World in 1494—is challenging the long-held notion that the site is where Europeans first mined and processed precious metals in the New World. A recent lead isotope analysis of La Isabela artifacts reveals that the settlers were not, as archaeologists thought, extracting silver from Caribbean ores but were trying to pull the metal out of materials they'd brought from Spain (Proc. Natl Acad. Sci USA, DOI: io.i073/pnas.o6o7297i04).

The discovery provides new evidence of how desper­ate La Isabela's inhabitants were to extract something of value from their disastrous time in the New World, says Alyson M. Thibodeau, the geosciences graduate student at the University of Arizona who spearheaded the research.

La Isabela has a legacy of disappointment. When Columbus returned to Spain in 1493 from his first expedition to the Americas, he spoke exuberantly of a New World glimmering with golden treasure. His tales convinced Spain's King Ferdinand and Queen Isabella to finance a much larger second expedition. As many as 1,500 settlers joined Columbus, no doubt tempted by the promise of riches.

These starry-eyed adventurers established La Isa­bela, the first European town in the New World, on the northern shore of what is now the Dominican Republic.

They did not, however, find any precious-metal ores there. Instead, the settlers found hunger, disease, hurricanes, mutiny, and conflicts with the local Tamo natives. By 1498, La Isabela had been abandoned.

While excavating La Isabela in the late 1980s and early 1990s, archaeologists unearthed evidence of silver extraction. They found more than 100 lb of galena, a sil­ver-containing lead ore, as well as hundreds of pounds of slag, which, upon close inspection, contained tiny specks of silver. This, the archaeologists thought, indicated the settlers' early silver-prospecting efforts.

But one question remained: Why didn't the set­tlers' records mention any discoveries of ore? Thibodeau decided to compare the lead iso­tope ratios from galena deposits in the Carib­bean with those from the galena from La Isa­bela. They didn't match. But lead isotope ratios

from the La Isabela galena did match those of Spanish samples of the ore, leading Thibodeau to conclude that the settlers brought the material with them, probably to compare with the anticipated local ores for a rough assay of silver content.

"What appeared to be the earliest evidence of Euro­pean finds of precious metals in the New World turned out not to be that at all," says David J. Killick, an anthro­pology professor at Arizona, who participated in the research. "It's a very different story."

Piecing together what's known about La Isabela's final doomed months and the poorly processed galena, Thibodeau's group hypothesizes that the settlement's last desperate survivors were trying to salvage anything of value before abandoning the site.

"This part of the story of Columbus' failed settle­ment is one that couldn't be found in the historical documents," Thibodeau says. "We never could have fig­ured this out without applying the techniques of physi­cal science to the archaeological artifacts."—BETHANY HALFORD

Galena and leadpieces unearthed at La Isabela,

HAZARDOUS WASTE Facilities have been unequally sited in poor, minority communities

University of Michigan researchers now think they have answered a long­standing chicken-and-egg question: Which came first, the hazardous waste facility or the poor, minority community surrounding it?

Over the past 20 years, environmental justice scholars have argued that such fa­cilities have been disproportionately sit­ed in politically powerless, poor, minority neighborhoods. Others have claimed that the hazardous waste facility came first, and the demographics of the area shifted as the richer white population fled.

Using more refined methods than the

older census-tract methodology, Paul Mohai, a professor of natural resources and the environment, and Robin Saha, a former postdoctoral scholar, have been able to show that minorities were living in the areas before the facilities arrived.

Although demographic changes lead­ing to more minority-centered neigh­borhoods did occur after the facilities arrived, these changes had already begun before the facilities came, Mohai says.

"I think my findings are important be­cause they tend to support the claims of the environmental justice movement that poor, minority communities are targeted

for things like hazardous waste facilities and other kinds of locally unwanted land uses ," Mohai tells C&EN. "They also sug­gest that there ought to be some consid­eration given to monitoring and manag­ing the siting process so that poor com­munities of color are not overburdened with facilities that they don't want."

Bills have been introduced in the House and Senate that would force the Environmental Protection Agency to implement former president Bill Clinton's 1994 environmental justice executive or­der that mandates correction of environ­mental inequities.—LOIS EMBER

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