A recently unveiled map purporting to show a Chinese explorer discovered America in 1418 has been met with skepticism from cartographers and historians.

An inscription identifies the map as a copy made in 1763 of an original drawn in 1418.

Antiquities collector Liu Gang, who unveiled the map in Beijing last week, says it proves Chinese seafarer Zheng He discovered America more than 70 years before Christopher Columbus set foot in the New World. He said he purchased the map in 2001 from a Shanghai dealer for $5,000.

But experts have dismissed the map as a fake, saying it resembles a French 17th-century world map with its depiction of California as an island, National Geographic News reported Tuesday. That China is not shown in the center also suggests the Chinese did not make the map, one expert said.

"If this is a 1418 map, it's a whole style very much different than any 1418 map that I've seen," John Hebert, chief of the Geography and Map Division at the Library of Congress, told National Geographic News.

New Zealand scientists are radiocarbon-dating a scrap of the map's bamboo paper to determine its age.

Copyright 2006 by United Press International