Provenance studies on façon-de-Venise glass excavated in Portugal

One group comprising fragments from São João de Tarouca Monastery, presented medium alumina contents, differing from known façon-de-Venise production centres. The other group includes most fragments from Miguel Fernandes Square assemblage and has high alumina values, which, once again, is not consistent with any of the known façon-de-Venise production centres. For these reasons, the existence of new façon-de-Venise production centres is proposed.