King Tut's glorious iron dagger is made from a meteorite

An inconsequential iron dagger? 

Compared to the coffin and burial mask made of gold, thrones, pieces of furniture, a lotus chalice, and many others found in King Tut's tomb, an iron dagger might seem inconsequential. However, it is one of the few things among his belonging that is made out of iron. 

Archaeologists believe that back in those days, iron was a symbol of high status in society. From the data available so far, we know that smelting was not very common in the region, and working with metallic iron dates back to a few hundred years before the pharaohs became rulers of the unified state. The Iron Age is believed to have begun around 1200 BC, a century after King Tut passed away. 

A 2016 research used X-ray fluorescence spectroscopy to study the composition of the material and found high traces of nickel in the principal component iron. While nickel traces in terrestrial iron does not exceed four percent, the 11 percent nickel content in the blade pointed towards the extra-terrestrial origin of the starting material, most likely a meteorite.

Origins of the dagger

Unlike other iron items found in the tomb, the dagger's build rose further questions about its origins. Takafumi Matsui and his colleagues at the Chiba Institute of Technology in Japan wanted to further understand the dagger's origins and visited the Cairo Museum in February 2020. 

Using a portable scanning X-ray fluorescence instrument, the researchers obtained a high-resolution optical image of the dagger. Apart from the traces of nickel and cobalt as were found during the 2016 study, the researchers also found traces of sulfur, chlorine, calcium, and zinc in the form of blackened spots on the blade, Ars Technica reported. 

The distribution of these trace elements follows a pattern called the Widmanstatten pattern, regularly seen in iron meteorites. The researchers could confirm this by comparing the patterns on the dagger to those on another meteorite in Japan. 

From the low amounts of sulfur in the blackened spots, the researchers conclude that the dagger was forged at a relatively low heat of 1,724 degrees Fahrenheit (950 degrees Celsius). 

Using diplomatic correspondence available in the Egyptian royal archives, the researchers have traced the dagger back to King Tut's grandfather Amenhotep III, who received it as a marriage gift from the King of Mitanni. The gemstones in the dagger have been attached with lime plaster that was used in Mitanni during those times, while Egyptians used gypsum plaster. 

The research findings have been published in Meteorites and Planetary Science.  

Study Abstract: 

The Iron Age was the time when people acquired iron processing technology and is generally thought to have begun after 1200 B.C. Some prehistoric iron artifacts made of iron meteorites are dated from the Bronze Age. A nicely preserved meteoritic iron dagger was found in the tomb of King Tutankhamen (1361–1352 B.C.) of ancient Egypt. Yet, its manufacturing method and origin remain unclear. Here, we report nondestructive two-dimensional chemical analyses of the Tutankhamen iron dagger, conducted at the Egyptian Museum of Cairo. Elemental mapping of Ni on the dagger blade surface shows discontinuous banded arrangements in places with “cubic” symmetry and a bandwidth of about 1 mm, suggesting a Widmanstätten pattern. The intermediate Ni content (11.8 ± 0.5 wt%) with the presence of the Widmanstätten pattern implies the source meteorite of the dagger blade to be octahedrite. The randomly distributed sulfur-rich black spots are likely remnants of troilite (FeS) inclusions in iron meteorite. The preserved Widmanstätten pattern and remnant troilite inclusion show that the iron dagger was manufactured by low-temperature (<950 °C) forging. The gold hilt with a few percent of calcium lacking sulfur suggests the use of lime plaster instead of gypsum plaster as an adhesive material for decorations on the hilt. Since the use of lime plaster in Egypt started during the Ptolemaic period (305–30 B.C.), the Ca-bearing gold hilt hints at its foreign origin, possibly from Mitanni, Anatolia, as suggested by one of the Amarna letters saying that an iron dagger with gold hilt was gifted from the king of Mitanni to Amenhotep III, the grandfather of Tutankhamen.