On Wednesday, March 25, 1981, it was announced that the lost treasure of Moctezuma had been discovered. Well, a small part of it, at least.

This legendary treasure has long captivated the imagination. In the 16th century, the conquistador Hernán Cortés arrived in Tenochtitlan (the present-day center of Mexico City) and stayed at the Palace of Axayacatl. There, he and his men discovered a room in which the Aztecs kept their emperors’ treasures.

Cortés continued staying in the palace, eventually taking the Aztec ruler Moctezuma hostage. After Moctezuma was killed when his people revolted against both him and the Spanish, the conquistadors fled the city. Before they left, they made sure to pack a hefty portion of the golden treasure.

The Spaniards were discovered during their escape. The men, bogged down with pounds of treasure, struggled to fight. As the bridge they were crossing was destroyed, some of the men—and the priceless items they were smuggling—sank in the waterway.

Cortés returned to the city months later, forcing the Aztecs to surrender. But he never saw the coveted treasure again. For centuries, people scoured far and wide for hints of the treasure. It wasn’t until 1981, when construction on a bank was happening, that a golden brick engraved with a crown was discovered. Anthropologists believe the hunk of gold was molded so it would fit inside a fleeing Spaniard’s armor. The brick is now displayed in a modest showcase in the National Museum of Anthropology, near a block of information that hardly touches upon its legendary history.