UNESCO discounts American explorer's claim of discovery of pirate treasure in Madagascar

The United Nations is rejecting the assertion of an American underwater explorer who says his search in Madagascar uncovered a silver ingot that belonged to 17th century pirate Captain Kidd.

The U.N. cultural body UNESCO said Tuesday that the so-called silver ingot is actually a piece of ballast that consists almost entirely of lead.

In May, explorer Barry Clifford presented what he said was the silver ingot to Madagascar's president in a ceremony on the island of Sainte Marie, near the country's northeast coast. Clifford's diving team had said the bar was found in a bay off the island.

UNESCO then sent a team to Madagascar to investigate.

William Kidd, known as Captain Kidd, raided ships before being captured and executed in London in 1701.