Ancient shipwreck reveals oldest known raw iron cargo at sea

Thursday 26 March 2026 - 08:20

By: Dakir Madiha

Ancient shipwreck reveals oldest known raw iron cargo at sea

Researchers from University of Haifa have uncovered what they describe as the oldest known shipment of raw iron transported by sea, dating back about 2,600 years. The discovery was made during an underwater excavation off Israel’s northern Mediterranean coast, in the Dor lagoon near the Carmel shoreline.

The team recovered nine pieces of unprocessed iron, known as blooms, from a shipwreck. The findings were published in Heritage Science, part of the Nature portfolio. The iron pieces show no signs of forging or further shaping, indicating they were shipped in their raw state directly after smelting.

This challenges long-standing assumptions about ancient iron trade. Experts had believed that iron was typically processed into usable forms at production sites before transport. The Dor lagoon discovery suggests instead that raw iron was moved across regions and refined at its destination.

Professor Tzilla Eshel, who led the study, said the cargo provides the earliest archaeological evidence of maritime transport of iron blooms in their original form. Unlike copper or bronze, iron could not be melted into liquid in ancient furnaces. Instead, it was produced as a solid, porous mass containing slag, which blacksmiths would normally hammer to remove impurities.

Radiocarbon dating of a charred oak fragment embedded in one of the blooms places the cargo in the late 7th or early 6th century BCE. This period saw shifting control of the region among the Assyrian, Egyptian, and Babylonian empires. Eshel noted that the timing likely reflects strong demand for iron during a period of regional conflict and resource competition.

Each bloom weighs between five and ten kilograms and remains well preserved. A layer of slag formed a natural protective barrier, preventing corrosion and keeping the metal intact for over two millennia underwater.

Professor Aren Maeir of Bar-Ilan University, who was not involved in the research, said the discovery confirms that iron production and forging could take place in separate locations. The finding offers new insight into the structure of ancient trade networks.

The shipwreck is one of three Iron Age cargo sites identified in the Dor lagoon, spanning from the 11th to the 6th century BCE. Earlier findings from the site were documented in the journal Antiquity. Researchers plan further excavations to determine the geographic origin of the iron and better understand regional trade routes.