REUTERS unearths the details:
"The bar was originally discovered in 1981 during a construction project some 16 feet (5 meters) underground in downtown Mexico City - which was built on the ruins of the Aztec capital Tenochtitlan - where a canal that would have been used by the fleeing Spaniards was once located.
The bar weighs about 2 kg (4.4 lb) and is 26.2 cm (10.3 inches) long, 5.4 cm (2.1 inches) wide and 1.4 cm (half an inch) thick.
A fluorescent X-ray chemical analysis was able to pinpoint its creation to between 1519-1520, according to INAH, which coincides with the time Cortes ordered gold objects stolen from an Aztec treasury to be melted down into bars for easier transport to Europe.
Historical accounts describe Cortes and his men as heavily weighed down by the gold they hoped to take with them as they fled the imperial capital during what is known today as the “Sad Night,” or “Noche Triste,” in Spanish."
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