Analytical investigation and electrochemical conservation treatment for archaeological copper alloy artifacts from Jordan

Abstract

This study presents an analytical investigation and electrochemical conservation treatment for a group of four copper alloy artifacts excavated from the archaeological cemetery that was located on the site of the Queen Alia International Airport, Jordan. The chemical analyses of internal alloys showed that a bracelet and a spatula were made of a quaternary copper–zinc–tin–lead alloy, a bracelet was made of a copper–silver–zinc alloy, and a spatula was made of a copper–tin, a bronze alloy. The corrosion products analyses indicated the presence oxides, carbonates and chlorides of copper, in addition to silver chlorides for the copper–silver–zinc alloy bracelet. The metallographic examination showed various degrees of working and heat treatment in the manufacturing process of the artifacts. The potentiostatic reduction technique was effective in reducing the corrosion products on the artifacts, which were finally coated with Paraloid B–72 to prevent corrosion reoccurrence.