The first known masks are Halloween-like stone portraits of the dead, according to an upcoming exhibition at the Israel Museum in Jerusalem.

The exhibit, called Face to Face: The Oldest Masks in the World, reveals for the first time 12 Neolithic masks featuring wide toothy smiles and large eyes.

According to the curators, who set up the display after 10 years of investigative work, the eerie stone portraits were carved out of limestone some 9,000 years ago by Stone Age people who were among the first to abandon nomadic life.

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Analysis into the type of stone revealed the masks came from the Judean Hills and nearby Judean desert in Israel. Although there is no record of their use — they predate writing by 3,500 years — experts believe the artifacts might represent various ancestors of an early Stone Age religion.

“It is important to say that these are not living people, these are spirits,” Debby Hershman, curator of prehistoric cultures at the Israel Museum who organized the exhibit, told the Times of Israel.

The masks were probably used in rites of healing and magic and in ceremonies celebrating the deceased. They weigh about 2 to 4 pounds and likely would have been painted, as the color traces on one of them suggest.

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Each of the 12 masks is unique, and shows old and young faces of various size. One even resembles a human skull.

“They are the first glimmerings of existential reflection,” James Snyder, the museum’s director, told the Times of Israel.

Several masks feature a set of holes along the outer edge, as if they were hung or worn.

The exhibition runs from March 11 until Sept. 13 and ”will be an opportunity for investigation, research, reflection, conjecture,” Snyder said.

Photo: Neolithic masks were carved out of limestone some 9,000 years ago by Stone Age people. Credit: Israel Antiquities Authority. Exhibited at The Israel Museum, Jerusalem