Palmierite (and atacamite?)

[Jorge_Stolfi]

There is no assessment of the likelihood of the palmierite scenario, because that's not expected of the report.

And, by the way, hey have one X-ray instrument that can tell how much of each element is there in the sample, but not in which chemical form.  

The instrument that detected palmierite is a different one, that directs a fine beam of X-rays onto a microscopic particle taken from the sample, and measures how much of the beam is scattered in which directions as the particle is turned.  If the particle contains a single crystalline substance, that data is a spectrum (like that on page 2 of the report) whose peaks depend on the spacing and arrangement of atoms in the crystals of that substance. The software then scans a large library of spectra of minerals and reports the best match (azurite in the case of page 2).  

But that only identifies the crystalline substance in that particle that was analyzed. It cannot tell how much of that substance is present in the paint.  Probably not even in that particle.  And it cannot identify non-crystalline substances (like iron-gall ink, or the green pigment most used in the VMS).  And there may be several spectra in the library that are equally good matches to the data, within the limits of the noise; but the software apparently prints only one...

All the best, --stolfi