Lapis Lazuli Particles on the Turin Shroud: Microscopic Optical Studies and SEM-EDX Analyses

Abstract

We have studied by optical microscopy and SEM-EDX lapis lazuli particles adhering to a sample of the Turin Shroud. A total number of seventy lapis lazuli particles (and sub-particles) were found on the surface of this sample, and were characterized in details: they are little particles (of between 0.1 and 15 μm of maximal length), of blue colour, and with a spectrum of chemical elements identical to that of the lapis Lazuli mineral. We hypothetise that these particles are residues of painting layers of lapis lazuli that covered initially the Turin Shroud.