Penelope Clifford & Vic Semeniuk 
Patina on Historic Glass [PDF ebook] 
A Case Study from Cossack, Western Australia

This book explores patina, a micro-crust of interlaminated silica and calcite developed on bottle glass that was partially buried for 70-100 years in dunes at Cossack, Western Australia, and is a world-first in the detailed, holistic study of this phenomenon. It maps out a multifaceted approach involving soil chemistry, granulometry, mineralogy, soil water hydrochemistry, glass chemistry, SEM mapping of patina, and XRD and SEM/EDS analyses, as well as experimental leaching and pellicular water analyses of sand and dust in which the glass was embedded to highlight that, to fully use patina for archaeological, hydrochemical, geochemical, and climate studies, there must be a multidisciplinary approach. The patina on glass from Cossack yielded a wealth of micro-structures providing insights into the processes of its formation. Patination is complex, reflecting wet and dry vadose conditions, alternating acid and alkaline conditions, and requiring many factors to be taken into account to obtain a comprehensive understanding of its development. In practical terms, properly used, patina and its internal structures can date glass for use in archaeology, determine soil and hydrochemical processes of solution, precipitation, and illuviation, and unravel local intra-decadal climate patterns. The weathering metastability of glass also points to potential problems in recycling glass for use in infrastructure, construction materials, and containers for toxic waste and nuclear waste.