On-site Raman analysis of Medici porcelain

On-site Raman analyses were performed at the Musee National de Ceramique, Sevres, France, on the rare, first-known European porcelain dishes, produced from 1575 to 1587 in Florence, under the patronage of Grand Duke Francesco I de Medici. The results are discussed in the light of previous chemical analyses. The different identified phases are a-quartz, feldspar, calcium phosphate and beta-(and alpha-) wollastonite, i.e. the fingerprints of both hard- and soft-paste porcelains. The presence of feldspar is consistent with the high potassium and aluminium content, evident from previous composition analysis. The good dissolution of quartz grains and the signature of beta-wollastonite (CaSiO3) are consistent with a frit-ware technology. Calcium phosphate in the enamel indicates that the Islamic technique of opacification with calcined bone was used. Copyright (C) 2003 John Wiley Sons, Ltd.