Scientists Have Been Trying to Understand How Ancient Egyptians Created Mirrors For Years. It Looks Like They Finally Figured It Out

Throughout history, mirrors have always been a source of fascination in different cultures. It makes sense, at least for humans, the only animals capable of recognizing their own reflection next to apes. The word “mirror” comes from the Latin word “mirare,” which means “to marvel.” The oldest known manufactured mirror dates back to around 6000 B.C. and was found in a late Neolithic site in Turkey. But what about mirrors in Ancient Egypt?

A recent study. A team at the University of Liverpool in the United Kingdom has recently published an interesting study in the Journal of Archaeological Science: Reports. Led by researcher Elizabeth Thomas, the group embarked on the study with the understanding that mirrors played a crucial role in both cultural and religious aspects of Ancient Egyptian society. However, little was known about how they were made until now.

The results have revealed the craftsmen’s extensive knowledge of metallurgical techniques and their use of three main types of alloys in manufacturing: arsenical copper, tin copper alloy, and arsenical copper-tin ternary alloy.

Chemical analysis. Thomas mentions that they studied the known facts before starting their work. Specifically, in Ancient Egypt, mirrors were highly polished copper, bronze, or gold discs representing the Sun. The handles of these mirrors were shaped like papyrus stems or the figure of Hathor, the Egyptian goddess associated with beauty and rebirth.

The researchers’ first step was to analyze the metallurgy of nineteen Egyptian mirrors, covering a wide chronological period from the Old Kingdom to the Late Period. They used a scanning electron microscope with an energy-dispersive X-ray spectrometer (SEM-EDX) to analyze the chemical composition and microstructure of the ancient artifacts. This allowed them to uncover hidden secrets about the construction of these mirrors that have been unknown for thousands of years.

The three keys. As previously mentioned, Ancient Egyptian artisans consistently used three types of alloys when making mirrors: arsenical copper, tin copper alloy, and arsenical copper-tin ternary alloy. In fact, the study also reveals that the composition was consistent, with the mirrors analyzed containing approximately 5% arsenic or tin.

What does this mean? The team suggests that it indicates a high degree of control and standardization in the manufacturing process, much higher than previously known. In fact, such consistency not only confirms how skilled the Egyptian craftsmen were at their job but also raises other questions. For example, why use that specific alloy and not another?

A possible explanation. Thomas and her team believe that the Egyptians used this specific composition because the metal has optimal physical properties, such as hardness and malleability. Another possible explanation is the color, which supposedly allowed them to achieve the desired golden or silver tone in the finished mirror.

In fact, the paper contains evidence of a technique known as surface enrichment, which involves creating a surface layer rich in arsenic. This process would give the mirrors a shiny and silvery appearance, possibly to make them look similar to more valuable materials like silver.

A remarkable technique. Thomas explains that the surface enrichment of this type of metallurgical technique was most likely achieved through a process known as inverse segregation. This sophisticated technique required intricate knowledge of the metallurgical properties of arsenical copper. Regarding the choice of alloys, the team suggests that religion could be a key factor in determining whether the Egyptians preferred golden or similar reflections.

Finally, the recent study also uncovers something surprising. Microscopic analysis revealed clues about an unusual manufacturing process for the time. It involved repeated cycles of cold hammering and annealing, leading to a higher metal hardness. This allowed for better polishing and a clearer, more consistent reflection.

It appears that the Egyptians had a well-established craft metallurgy industry much earlier than previously imagined.

Image | Metropolitan Museum of Art (Public Domain) | M abnodey (via Unsplash)

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