After being unable to see some of the ink on our parchment scrolls we began a study into which of our collection of parchment samples had iron present and which did not. To assess the level of iron present in our parchment samples we used X-ray fluorescence (XRF). XRF is an excellent non-destructive analytical technique for chemical analysis. An example spectra collected from two of our parchment samples is shown below where a clear iron peak is visible in the one sample and is missing in the other sample.
We found that most of our parchment collection had a presence of iron to a certain degree but using XRF we have now identified which parchment samples had a low fraction making them difficult to see.