Identification of corrosion products on a medieval copper-silver coin

• Type: Article in International Scientific Journal
• Date: 2011

Authors

C. M. B. Martins (Author) FEUP; José Inácio Martins (Author) FEUP

Journal

Title: Protection Of Metals And Physical Chemistry Of Surfaces

Vol. 47 No. 1

Pages: 128-132

ISSN: 2070-2051

Publisher: Pleiades Publishing

Indexing

ISI Web of Knowledge - 10 Citations

ISI Web of Science

Scopus - 13 Citations

Scientific classification

FOS: Engineering and technology > Chemical engineering

Other information

Authenticus ID: P-002-XSP

DOI: 10.1134/s2070205110061012

Abstract (EN): This work relates a study on a medieval coin found during archaeological works carried out at the site of Senhora do Castelo in Urros (Torre de Moncorvo, Portugal). The artefact has been identified as a coin of D. Afonso IX of Leon (1155-1188). The substratum showed composition typical of bullion, Cu-Ag (30-33%) with minor elements (1% Pb + 0.2% Sn + 0.4% Zn). The corrosion products developed on the coin during the archaeological burial was studied by means of optical microscopy (OM), scanning electron microscopy combined with energy dispersive spectrometry (SEM-EDS), energy dispersive X-ray fluorescence (EDXRF), and X-ray diffraction (XRD). The results show the presence of cuprite, atacamite, chalcocite, native silver, silver oxide and silver sulphide on the outer layers of the coin, which allows deducing the importance of the environment in the corrosion phenomena.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 5