Abstract:
Raman spectroscopic analysis of shards recovered from two Portuguese shipwrecks, the Santo Espirito (1608) and the
Santa Maria Madre de Deus (1643), believed to be carrying porcelains of the Ming period have revealed some interesting
and novel results that inform historical ideas of porcelain production. The porcelain body of two of the four
shards from the Santa Maria Madre de Deus were found to contain anatase, a low temperature polymorph of titanium
dioxide, and β-wollastonite a mineral characteristic of soft-paste porcelains that are made at medium-temperature
firing conditions. Previously, β-wollastonite has been found in a range of sixteenth to nineteenth century European
porcelains but this is the first report of its detection in porcelain believed to be from the Ming period. These same
shards exhibited unusual spectral features that were attributed to the resonance enhancement of rare earth elements
that resulted from excitation using a near-infrared source.
