Mexico’s National Institute of Anthropology (INAH) says it has now confirmed that a 1.93-kilogram gold bar was part of looted Aztec treasure (AFP Photo/Jesus VALDOVINOS)

A gold bar, found 15 feet down in a Mexico City park in 1981, was just announced to have been part of Montezuma’s treasure. Mexico’s National Institute of Anthropology and History completed a specialized chemical analysis of the bar and discovered that it is from the time period of Montezuma, and likely fell into an ancient canal on the “Noche Triste”, or “Sad Night”in 1520.

The bar weighs about 4.4 pounds (1.93 kilograms) and is 11 inches long (26 centimeters) and is three fingers in width. It is part of the collection of the National Museum of Anthropology (MNA).

The New York Times

April 19, 1981

A four-pound gold bar found on a building site in downtown Mexico City last month is believed to be part of the treasure seized from the Aztec Emperor Montezuma II by the Spanish conquistador, Hernan Cortes, in 1520.

The discovery has stirred great excitement among Mexican archeologists because it is the only remnant of the legendary treasure ever found here. Now on display in the National Museum of Anthropology, it is being viewed daily by thousands of Mexicans.

The concave rectangular bar, which contains 22.5-carat gold with a market value of $25,000, was picked out of mud 15 feet below street level on March 13 at a site where a new office block is being built by the Bank of Mexico, today’s guardian of the country’s gold.

The bar, 10.4 inches long, 2 inches wide and 0.4 inches thick, was handed to archeology students who are normally stationed at large building sites where pre-Hispanic artifacts may be unearthed. ‘No Evidence’ of More

The bar, though, is not expected to lead to the discovery of more of the treasure. ”There are all sorts of myths about the treasure of Montezuma, but Cortes got all there was,” Gaston Garcia Cantu, director of Mexico’s Anthropology and History Institute, said. ”There is no evidence to suggest that there is a treasure hidden or lost somewhere.”

Montezuma’s treasure was his inheritance upon becoming ruler of the Aztecs in 1502. Word of the treasure soon reached Cortes when he landed on the Veracruz shore in 1519. The following year, after being welcomed to the Aztec capital of Tenochtitlan, the conquistador arrested Montezuma and demanded all his gold.

At the time, the gold was still in pots, art objects, jewels and clothes. Bernal Diaz del Castillo, one of Cortes’s captains, wrote in his memoirs, ”With the help of the Indian goldsmiths from Atzcapotzalco, we began to melt this down into broad bars a little more than two inches across.”

Squabbling among themselves, the Spaniards divided the treasure, with one-fifth going to King Charles V of Spain and one-fifth to Cortes. In June 1520, though, there was an Indian uprising in which Montezuma was killed, and the conquistadors decided to flee Tenochtitlan, now Mexico City. Some Gold Lost in Attack

Cortes assigned carriers for his gold and the royal portion. Diaz del Castillo recalled his words: ”Bear witness for me that I can do no more with this gold. It cannot be weighed or brought to safety. I now give it over to any soldiers who care to take it. Otherwise we shall lose it to these dogs.”

On the night of June 30, 1520, later to become known as the sad night, the Spaniards and their Tlaxcalan Indian allies began moving along the causeways across Lake Texcoco out of Tenochtitlan. The Aztecs learned of their flight and attacked. ”The channel or water gap was soon filled with dead horses, Indians of both sexes, servants, bundles and boxes,” Diaz del Castillo recounted. In the chaos, some of the gold was lost.

The place where the gold bar was found last month coincides with the site of a canal along a causeway in 1521. Containing 93.98 percent of gold, 5.24 percent of copper and 0.78 percent iron, the bar was also the result of a rushed foundry job, consistent with the melting process described by Diaz del Castillo.

Most of the treasure survived the sad night and much of it went to Spain. ”It was used to finance the Spanish wars in the Netherlands and against England and Italy,” Mr. Garcia Cantu noted.