Characterization of the microstructural features and the rust layers of an archaeological iron sword in the Egyptian Museum in Cairo (380–500 A.D.)

Abstract

In this paper, a sword is investigated from a collection of archaeological iron swords displayed in the Egyptian Museum from the civilization centered on Ballana and Qustul in Egyptian Nubia (380-600 A.D.). A range of metallographic analytical techniques have been used to characterize the sword's metallic structure and its rust crust. The results revealed that the sword was made of low-carbon steel and corrosion products formed on the surface are iron sulfate, iron oxides/hydroxides including goethite, maghemite, magnetite, lepidocrocite, akaganeite and ferric chloride. The investigation also revealed that the rust crust constituted of two corrosion layers: a dense layer and a transformed medium. Crystals of soil minerals were clearly observed in the outer corrosion layer. Moreover, several microstructural features were detected, indicating the stage of deterioration and the features of metallurgy of this sword. Furthermore, the obtained results have been used to select appropriate conservation procedures for preventing degradation in the future and ensuring its reliable restoration.

A comprehensive strategy for exploring corrosion in iron-based artefacts through advanced Multiscale X-ray Microscopy

“…Indeed, the main phase observed at the interface between the metal and the rust layer is goethite. The formation of the TM, in red, could be explained by the dissolution of iron and reprecipitation of iron corrosion/oxidation products over the surface of the object, perhaps over the original surface 27 , 30 – 33 .…”

Experimental Study on the Corrosion of Carbon Steel and Aluminum Alloy in Firefighting Protein Foam Concentrates

“…Forms of other ferric oxyhydroxides, such as reddish-brown lepidocrocite (γ-FeOOH) and goethite (α-FeOOH fine crystallites with fibrous structure) were also reported as the main phases of corrosion layers together with FeOCl compound, and amorphous rust [ 53 ]. On contrary, an abundant literature has been published on corrosion of stainless steel in protein-containing media [ 54 , 55 , 56 , 57 , 58 ] whereas much less work has been dedicated to pure Fe [ 55 , 59 , 60 ]. For ferrous material surfaces, it is unanimously accepted that both physisorption and irreversible chemisorption of proteins may be possible and iron oxides formed on the surface will facilitate protein aggregation around the defect sites.…”

An Unpublished Silver Toe Ring with A Fly (JE 70385)

“…4). Both cemeteries are in Lower Nubia, on the boundary between Egypt and Sudan, between the first and second cataracts of the Nile (Salem et al, 2019). After the construction of the High Dam, the original location of the Ballâna cemetery has been drowned by Lake Nasser's water (Lobban, 2003).…”