Wednesday, March 28, 2018

Maurizio Aceto and Scientific Analysis of Manuscripts

The John Rylands Library is running an exhibit through August 2018 called The Alchemy of Colour. They even have a series of short YouTube videos describing non-invasive ways that multi-spectral analysis can shed new light on manuscripts. The videos are a delight to watch.

One of the videos shows that cow’s urine was used for a particular yellow pigment—demonstrated by a yellow dress glowing under the blacklight. It sounds almost scandalous, but if you are familiar with ancient recipes for making inks and dyes, it really is no surprise. Earle Radcliffe Caley’s 1926 translation of P.Leiden X, for example, has six references to urine as an ingredient. The video that excited me, however, was a short discussion of the colour purple:

In the video, Cheryl Porter gives a great description of some of the ways purple was made and the significance the colour had in antiquity. She mentions specifically that purple was often equated with power. That has led some to suspect that purple Gospel books could have had political significance.

Rather than a discussion of the colour purple, however, I wanted to use the opportunity afforded by the video to point readers to some of the work being done by Maurizio Aceto. You might ask why Aceto appears in a video about the use of purple in manuscripts, especially because he doesn’t say anything about the colour.

Photo credit: John Rylands Library Special Collections Blog,
Purple is the new black“ (2 November 2017)
The reason is that Aceto has published several articles in recent years on the use of non-invasive scientific testing to learn about ancient artefacts, and purple codices have been subjects of a number of them. In one of his publications (“First Analytical Evidences of Precious Colourants on Mediterranean Illuminated Manuscripts), he and a team of researchers used Raman spectroscopy, X-ray fluorescence spectrometry (XRF) and UV-Vis diffuse reflectance spectrophotometry with fibre optics (FORS) to identify the inks and colourants in the Vienna Dioscurides and Vienna Genesis manuscripts of the sixth century.

In another study (“Non-Invasive Investigation on a VI Century Purple Codex from Brescia, Italy”), Aceto led a team of researchers who used XRF, FORS and a couple of other non-invasive techniques on Codex Brixianus, a sixth-century Latin purple codex. This second article I mention was especially interesting, as Aceto et al. demonstrate that Tyrian Purple was not the main source of the purple dye, but they suggest that the codex might have been dyed by a process known as top-dyeing. The parchment was first dyed with a cheaper purple substitute, and then a thin layer of more expensive Tyrian purple was added on top of the lesser-quality dye. It was a way to save money without completely losing the colour of the more expensive dye. (Let me add that his suggestion about the possibility of top-dyeing applies only to Codex Brixianus, not necessarily to the Greek purple codices from the same era.)

I give the information for some of Aceto’s publications below. If you like manuscripts and dabble in science (or vice versa), they are interesting reads. Scientists like Aceto have a whole toolbox of equipment that can be used to study manuscripts that easily goes unnoticed by scholars concerned with the texts those manuscripts contain. Besides, science is fun!


Aceto, Maurizio, Angelo Agostino, Gaia Fenoglio, Pietro Baraldi, P. Zannini, C. Hofmann, and E. Gamillscheg. “First Analytical Evidences of Precious Colourants on Mediterranean Illuminated Manuscripts.” Spectrochim. Acta A 95 (September 2012): 235–45.

Aceto, Maurizio, Angelo Agostino, Enrico Boccaleri, and Anna Cerutti Garlanda. “The Vercelli Gospels Laid Open: An Investigation into the Inks Used to Write the Oldest Gospels in Latin.” X-Ray Spectrometry 37 (2008): 286–292.

Aceto, Maurizio, Ambra Idone, Angelo Agostino, Gaia Fenoglio, Monica Gulmini, Pietro Baraldi, and Fabrizio Crivello. “Non-Invasive Investigation on a VI Century Purple Codex from Brescia, Italy.” Spectrochim. Acta A 117 (January 3, 2014): 34–41.

Aceto, Maurizio, Angelo Agostino, Gaia Fenoglio, Ambra Idone, Fabrizio Crivello, Martina Griesser, Franz Kirchweger, Katharina Uhlir, and Patricia Roger Puyo. “Analytical Investigations on the Coronation Gospels Manuscript.” Spectrochim. Acta A 171 (January 15, 2017): 213–21.


  1. Please tell me that someone also tested the purple of Codex Argenteus the same way they tested the purple of Codex Brixianus.

    1. I think it's been carbon dated but not subjected to XRF (et al.). Though, there was an article in JTS (G. W. S. Friedrichsen, "The Silver Ink of Codex Argenteus) that suggested a similar cost-saving measure by thinning the ink to a lower concentration of silver for parts of the codex.