Chemical characterisation of glass mosaic tesserae from sixth-century Sagalassos (south-west Turkey): chronology and production techniques

Little is known about the origin, supply pattern and production technology of Byzantine glass mosaic tesserae. In this study, we have analysed forty-eight glass tesserae from Sagalassos (Asia Minor) of different colours and from two archaeological contexts that were stratigraphically dated to the sixth century CE. The main aim was to identify the raw materials, colourants and opacifiers as well as secondary working practices that are reflected in the composition (EPMA, LA-ICP-MS analyses) and the microstructure (XRD, SEM-BSE) of the tesserae. The set of samples retrieved from the Roman Baths complex at Sagalassos is compositionally very homogeneous, representing possibly a single commission, and can be tentatively dated to the late Roman period. In contrast, the assemblage associated with the construction of a Byzantine church around the turn of the sixth century CE is more diverse, suggesting that these tesserae were produced from more than one silica source. This highlights a diversification in the supply and manufacture of glass tesserae during the Byzantine period.     

Place leadership and the challenge of transformation: policy platforms and innovation ecosystems in promotion of green growth

ABSTRACT

In this paper, we explore how place leadership aims at producing transformational changes in the context of green growth. We ask what the main leadership strategies are that key actors pursue to gain leverage in their efforts to boost green growth. We use the well-known categories of transactional and transformational leadership. The following are the main research questions: (a) What do place leaders do to boost green institutional paths? (b) How do they aim to amplify their limited power base? and (c) How do they amplify their ability to influence both place-based and placeless agents? We scrutinize these questions in the context of green path development in two Finnish regions. The empirical study follows a two parallel single case study design. The cases in this paper deal with the cleantech-related path development in the Tampere city-region and bioeconomy-related path development in Central Finland. The two case studies were carefully chosen to illustrate the two main green growth-related industries in two different Finnish regions. The empirical data was based on 30 interviews of the national and local/regional development agencies as well as from firms and research/educational organizations. Additionally, the written material from the Internet, relevant journals, related newspaper articles and respective policy documents were analysed.