Casting cores used to craft large bronze masterpieces of the Florentine Renaissance and Mannerism

Archaeometallurgical characterisation of Donatello's Florentine copper alloy masterpieces using portable laser-induced plasma spectroscopy and traditional techniques

“…We carried out thorough investigations on the production of both works, reported elsewhere (Siano, 2005;Mugnaini et al, 2014). Here, let us briefly underline that from the technological standpoint both these unique works are strongly influenced by historic art foundry methods but for different reasons.…”

“…1386 -Florence, 13-12-1466) have had known conservation intervention treatments and related technical studies since the 1940s (Bearzi, 1951). Technological data were collected during the treatment of the following masterpieces: the funerary monument of Baldassarre Cossa (the antipope), Giuditta e Oloferne (Bearzi, 1951;Leoni, 1988;Europa Metalli, 1988), Amore Attis (Siano, 2005;Mugnaini et al, 2014), David , Mugnaini et al, 2014, Capitello, San Ludovico, and the Pulpito della Resurrezione. We had the opportunity to investigate the production processes and the alloy compositions of the last five of these sculptures.…”

Combined neutron and laser techniques for technological and compositional investigations of hollow bronze figurines

“…The fact that diffraction analysis did not detect probable original clay mineral compounds, such as kaolinite and/or montmorillonite, suggests that all the casting cores were heated at least at 850 C because kaolinite and montmorillonite dehydroxylate at 450 -600 C and 500 -750 C, respectively (See ref. 26 and references therein). Moreover, kaolinite could combine with calcite to form anorthite in the temperature range of 750-850 C. The presence of high temperature alumino-silicate phases such as mullite suggests that the three casting cores were red at a temperature above 1000 C. However, this value should be taken as rough indication of mullite formation because the mineral composition of the raw materials strongly inuences the formation temperature of mullite.…”

“…6Examples of TOF-ND measured (symbols) and calculated (solid line) diffraction patterns of detector bank N. 3. The fact that diffraction analysis did not detect probable original clay mineral compounds, such as kaolinite and/or montmorillonite, suggests that all the casting cores were heated at least at 850 C because kaolinite and montmorillonite dehydroxylate at 450 -600 C and 500 -750 C, respectively (See ref 26. and references therein)…”