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This paper proposes the application of digital image processing of plane- and cross-polarized light photomicrographs to textural and morphometric analysis as an extension of routine petrographic characterization. The aim is to answer questions on the provenance and technology of quartz- and calcite-bearing potsherds from the Takarkori rock shelter (Libyan Sahara, from around 8900 to 4200 uncal. years bp). Specific processing algorithms run on image analysis freeware (ImageJ) isolate quartz and calcite inclusions to obtain quantitative textural and morphometric data that are useful in identifying different local fluvial and swampy sedimentary environments as sources of sandy clays for pottery.

Fifty oil lamps from the catacombs of ‘Ponte della Lama’ (Canosa di Puglia, second to sixth centuries ad) were analysed to understand the correlations existing between types and fabrics and to determine their provenance. Petrographic and chemical analyses confirmed the archaeological hypothesis of local production of the oil lamps, using fluvial deposits. However, the three samples of oil lamps imitating the African ‘Atlante VIII’ are considered chemical outliers compared to the rest and are supposedly of foreign origin. The extensive and original repertory of lamp types characterizes Canusium as the production centre in the late Roman period.

Seventy-one oriented specimens from the pre-industrial reverberatory melting furnace of the Derriere Sairoche glassworks (Swiss Jura) were analysed. During its period of activity (1699-1714), this glassworks produced wood-ash glass of liquidus temperatures up to 1400°C. Textural and mineralogical features point to temperatures around 1500°C in the melting chamber. The inner structure of the furnace shows chemical contamination due to ash, molten glass and furnace gases. These results reveal the pyrotechnological know-how of the glassmakers and prove that the thermal performance of this kind of furnace has been under-evaluated in the past.