The long-standing mystery surrounding an ancient artifact often referred to as a “portal to the underworld” has been resolved, archeologists say.

The Olmec Cave Mask, a significant relic from the Chalcatzingo archaeological site in Mexico’s Central Highlands, was stolen in the 1960s. The mask, created between 800 and 400 B.C., was broken up by smugglers and the pieces scattered across various museums and private collections.

However, 2023 marked a significant year for the artifact, as it was finally returned to Mexico. In an August 2023 press release, the Manhattan District Attorney’s Office described the mask as depicting the Olmec jaguar god Tepēyōllōtl, characterized by its large oval eyes, flaring nostrils and gaping mouth.

The imposing mask was believed to guard the entrance to a ceremonial cave at Chalcatzingo, symbolizing the passage to the afterworld.

Late last month, Mexico’s National Institute of Anthropology and History announced that the examination of the artifact was nearing completion. The institute detailed the efforts of historians to clean and restore the mask, ensuring it was in the best possible condition for its return.

The institute noted that some parts of the mask date back 2,700 years, while others are more modern.

“Some elements that make it up are original, but others, such as a metal structure based on bolts, cement reinforcements and replacements of missing and shaped elements, they were added to give it stability again, although the techniques and materials were not the most suitable,” the group said in a press release translated from Spanish to English.

“We observe this through X-rays, but with a partial reading, given that X-rays do not penetrate enough due to the composition and structure of the stone.”

The Olmec Cave Mask soon will be returned to its home in Jantetelco, Morelos.

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