Computed Tomography and Roman Coins (mostly)

Interesting press release from Southampton which has been making the rounds of the news outlets in various forms … here’s the first three-quarters or so:

Archaeologists and engineers from the University of Southampton are collaborating with the British Museum to examine buried Roman coins using the latest X-ray imaging technology.

Originally designed for the analysis of substantial engineering parts, such as jet turbine blades, the powerful scanning equipment at Southampton’s µ-VIS Centre for Computed Tomography is being used to examine Roman coins buried in three archaeological artefacts from three UK hoards.

The centre’s equipment can scan inside objects – rotating 360 degrees whilst taking thousands of 2D images, which are then used to build detailed 3D images. In the case of the coins, the exceptionally high energy/high resolution combination of the Southampton facilities allows them to be examined in intricate detail without the need for physical excavation or cleaning. For those recently scanned at Southampton, it has been possible to use 3D computer visualisation capabilities to read inscriptions and identify depictions of emperors on the faces of the coins – for example on some, the heads of Claudius II and Tetricus I have been revealed.

University of Southampton archaeologist, Dr Graeme Earl says, “Excavating and cleaning just a single coin can take hours or even days, but this technology gives us the opportunity to examine and identify them quickly and without the need for conservation treatment at this stage. It also has potential for examining many other archaeological objects.

“The University’s Archaeological Computing Research Group can then take this one step further – producing accurate, high resolution CGI visualisations based on scan data. This gives archaeologists and conservators around the world the opportunity to virtually examine, excavate and ‘clean’ objects.”

Dr Roger Bland, Head of Portable Antiquities and Treasure at the British Museum comments, “This scanning technique is already yielding some fascinating results and the possibility of identifying a hoard of coins in a pot, without removing them, is very exciting. Working with archaeologists and engineers at Southampton, it is exciting to be pioneering and exploring the potential of a process which is faster, cheaper and less interventive than excavation.”

The three objects examined at Southampton are:

• A cremation urn containing nine coins, dating from AD282, found in the Cotswolds. This item in particular would take months to excavate – with archaeologists needing to carefully examine bone fragments and remains to extract more information about its past.

• An estimated 30,000 Roman coins discovered in Bath, dating to around AD270 and concreted together in a large block weighing over 100 kilograms
(radiograph image only).

• A small pot dating to the 2nd century found in the Selby area of East Riding in Yorkshire.

There’s also a link to this video, which shows the Selby material imaging:

Coincidentally, perhaps, earlier this week we were getting the protoclassicist in the family oriented down the 401 at Queen’s University, and while he and his mom were doing the tour of residences (with him excited and mom disgusted, of course), I wandered up to my old stomping grounds in Watson Hall to see if anyone was around. They weren’t, but I did notice a couple of important things. First, the departmental coffee lounge was rather smaller (and cleaner) than I remember it, and second, it was nice to see that some of the Queen’s people’s posters from conference poster sessions were adorning the walls (I think I’ve mentioned I’m a big fan of such things). Anyhoo, one of those posters was by Kate Sullivan, who appears to have just graduated from the Art Conservation program at Queen’s (which has ties to Classics, natch) and the subject of her poster was Comparing X-ray Computed Tomography Images of Corroded Coins with the Results from Traditional Cleaning … I made a note of the name and was very surprised when I got home to find this Southampton thing (on pretty much the same technology) in my box. Even better, though, I managed to find Kate Sullivan’s poster on the web as a pdf  … (more of these please!).

About these ads

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s