One-of-a-kind Iron Age mother-of-pearl seal unearthed at Tel Hadid, Israel

A tiny, iridescent shell seal found in an ancient garbage pit in Israel is the first of its kind ever found in the region and may have belonged to a community deported and relocated by one of the ancient world's mightiest empires thousands of years ago.

The oval stamp seal, carved from the shimmering inner layer of a sea mollusk, depicts an engraving of a crescent moon upon a triangle, a possible worshiper and an altar. Not only is the shell from which this seal was made not native to the region, but engraving the artifact also would have been particularly difficult, leaving behind a rare record of the tools and techniques used by an ancient artisan.

Dr. Ido Koch, an archaeologist at Tel Aviv University who led the study published in Levant, recalled receiving a radio call from his colleagues upon discovering the artifact. "At first, I found it difficult to believe, as I knew of no parallels," he said. But when an expert examined the artifact and confirmed that it was made of mother-of-pearl, "I realized we were dealing with something truly unique."

A seal like no other

The seal was discovered at Tel Hadid, a hill overlooking the central coastal plain of Israel. Recovered from a garbage pit, the surrounding pottery, animal bones, stone vessels and ash date the find to the seventh century B.C.

At the time, the Kingdom of Israel had been swallowed by the Assyrian Empire, leading to waves of people being deported and resettled across the provinces. According to the study, cuneiform tablets found at the site indicate that some of Tel Hadid's residents were likely newcomers, and the seal may have belonged to one of these deportees.

While stamp seals were typically used to authenticate documents and mark ownership, "the distinction between jewelry and a seal was not always a sharp one," said Koch, noting that seals could also be used as jewelry, set in rings or strung into necklaces.

Why mother-of-pearl? "The honest answer is that we do not know," Koch said. It is possible that its owner simply enjoyed its beauty, color or connection to the sea. The shimmering material would have set it apart from other, duller stamp seals, highlighting its wearer's special status, while its accompanying engravings gave it further symbolic meaning.

Clues engraved in shell

To understand how the seal was made, the researchers examined it with powerful microscopes and chemical analyses.

They found that while the drilled hole was made using a well-documented ancient shell-working technique, the engravings were much messier. Likely made with a bronze tool, the engraved lines varied in depth, and some appear to show where the artist slipped as they tried to work the shell without splintering or flaking its surface.

The image they engraved included a crescent shape sitting atop a triangle, beside a worshiper with a triangular body facing an altar. The odd shape of the worshiper and the fact that they face away from the moon motif suggest that the engraving may have started with just the two triangles and later added the other designs.

According to the study, the moon motif is similar to an emblem used for the moon god of Harran. This symbol was widespread across the Assyrian Empire and shows that the people of Tel Hadid deliberately chose to incorporate Assyrian imagery into local artifacts.

"The seal reminds us that the movement of materials, ideas and people across long distances was a normal part of life," said Koch.

Work at the site continues but has been hampered by regional conflict, which has kept some of Koch's colleagues away for three years. Despite this, local volunteers and visiting students continue the work of uncovering the site's complex history, with research spanning from the most recent village destroyed in 1948 to the ancient deported community that left a unique iridescent seal in a garbage pit more than 2,700 years ago.