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Thermally stimulated interactions between silver and glass, that is, silver dissolution as Ag + and precipitation as Ag 0 were studied in two glass series of molar target composition xAg 2 O-(19 − x)Na 2 O-28ZnO-53B 2 O 3 with x = 0, 0.1, 0.5, 5 and (19Na 2 O-28ZnO-53B 2 O 3 )+yAg 2 O with y = 0.01, 0.05. These act as model for low-melting borate glasses being part of metallization pastes. The occurrence of metallic silver precipitates in melt-quenched glass ingots demonstrated that silver dissolved only in traces (< 0.01 mol%) in the glasses. The dissolved silver was detected by means of Raman spectroscopy and energy-dispersive X-ray spectroscopy. Increasing x in the batch could not lead to a significant increase of the silver ion fraction in the glass as possible in binary silver borate glasses. In situ observation of heated AgNO 3 mixed with the base glass frit in a hot stage microscope showed that Ag 0 precipitation occurs already at the solid state. At higher temperatures, small droplets of liquid silver were found to move freely within the melt, whereas coalescence caused a stepwise increase of their size.These results contribute to the understanding of formation of silver precipitates in metallization pastes described in the literature.