Unique signatures

One of the most amazing things I love about research is that you are constantly learning, constantly exploring and driving forward understanding. I am so pleased to share a recent publication entitled Unique chemical parameters and microbial activity lead to increased archaeological preservation at the Roman frontier site of Vindolanda UK https://www.nature.com/articles/s41598-021-94853-7/metrics

The paper is open access and free to read, from scientific reports and here are five reasons why you should:-

  1. Microbes are fascinating and we understand so little about how they impact on preservation on artefacts
  2. Inorganic analysis – such as metals, play a huge part in the activity of microbes and thus preservation
  3. The diversity of microbes change depending on archaeological context.. and guess what this will impact on preservation
  4. The graphs are really cool
  5. It shows we need to understand the chemical and microbiological environment to understand our management practices for the future..

sample locations.

Slogging for Skelton

Just this week, our new paper on “Mapping an archaeological site: Interpreting portable X-ray fluorescence (pXRF) soil analysis at Boroughgate, Skelton, UK” was published! And so, we thought it would be nice to share some of the work that went toward this with you all.

Boroughgate was a 12th Century medieval borough in Skelton, North Yorkshire UK, near the All Saint’s Old Church and Skelton Castle. It was placed in the perfect location to support trade and income for the castle via but unfortunately it was unsuccessful and abandoned around 1400 CE. The remnants of earthworks at the site and medieval documentation recording some of the tradespersons at Boroughgate gave some clues as to the history of the site. Tees Archaeology went through a series of surveys before excavating the site, inviting us out to complete some pXRF analysis and explore whether pXRF elemental analysis can enhance and support their interpretations of the site. This was also an excellent opportunity for us to show the value of our method development for pXRF soil analysis in archaeology! Admittedly, this also may have been a bit of an excuse to get out on such a glorious Summers day…

Better get the sun lotion on because it’s a scorcher at Boroughgate!

pXRF is often seen as a rapid point-and-shoot method  but for good quality data, we really need an appropriate methodology. The soil matrix can vary greatly over just short distances, and we need to make sure that all our soil is examined in the same way, otherwise our comparisons are inconsistent and not well validated. We extract soil samples, dry them in the lab (preferably oven dried), grind down and sieve the samples so they’re nice and homogenous, and prepare them into pXRF sample cups. This does of course mean that we end up with a fair bit of soil samples in the lab from just one small area of soil..!

Nice selection of sorts sorted for scanning back at the lab

Research into social organisation and the activities or use of space from archaeological excavations uncover hidden knowledge on past societal practices and the structuring of historic communities. This work explored whether we could map out the elemental distribution of soil to identify different activity areas. This is discussed in much more detail in the journal article but just briefly, the distribution of aluminium, phosphorus, potassium calcium and iron distinguished between the internal dwelling and external area of a longhouse. Aluminium, potassium and calcium also distinguished a likely clean or food preparation area against a refuse area. These areas also aligned closely with the locations of artefacts such as pottery fragments, daub, and domestic or charred waste, as well as structural remains such as building foundation pads, postholes and wall foundations.

Summary of the pXRF interpretation. More pictures and diagrams in the paper!

This was a well worthwhile investigation into mapping pXRF of soil which we’re very excited to continue further. Don’t hesitate to contact us if you’re interested in surveying your site with pXRF, we’d love to see how much more we can learn about past communities with pXRF! Now before you go, don’t forget to say hi to the ridiculously sweet kitten which I’ve dubbed Sandy the Archaeology Cat because of its love for sitting in soil buckets and climbing over your shoulders judging your use of the Harris Matrix:

Sandy is the sweetest!

And finally, thanks to David Errickson at Cranfield University, and Tees Archaeology for inviting us out to your site!

TUBA

pXRF on pathology! Catching up with a student publication

Recently, we worked with Naomi Kilburn, a Master’s student at Durham University, whose dissertation project titled ‘Assessing pathological conditions in archaeological bone using portable X-ray fluorescence (pXRF)’ was published just this month! Fab, right? We took a moment from our calendar of Teams calls to have a Zoom call with Naomi and catch up on her work, experience, and the research.

Naomi Kilburn, the newly published researcher!
Hi Naomi! So first off, tell us about yourself – what’s your research passion?

My passion is for palaeopathology – I love looking at human skeletons to see what they can tell us about health, diseases, and life in the past.

Oh wow, fascinating! What area of palaepathology do you enjoy the most?

There are so many fascinating areas to explore, but… at the top are studying infant and childhood health and looking for ways to expand how we learn about health in the past.

What pathway did you take to get into palaeopathology?

I recently completed my master’s at Durham University and I’m currently working on securing some PhD funding so that I can keep asking (and maybe sometimes even answering) exciting questions about people and their bones.

So your paper, Assessing Pathological Conditions in Archaeological Bone using pXRF… how did that get started?

Well, this project came about through talking with Becky Gowland, my advisor at Durham, about possible dissertation projects.

Becky suggested portable X-ray fluorescence (generally called pXRF, as otherwise it’s quite a mouthful) as a way to combine studying children with a new palaeopathological technique.

My major research question was thus formed: Can pXRF be used to distinguish between different diseases in archaeological bone?

Mmm yes I can see how that idea was formed! Were you ready and raring to go or did you have a couple more hurdles to jump?

Ah yes, so, with the project idea settled, I then needed to figure out how to access a pXRF. Luckily, Becky knows many people and put me in contact with Tim Thompson at Teesside University.

After getting the go-ahead from Tim, I carefully packed some femora into boxes and headed to Teesside.

pXRF set up and ready to go.. safety first!
Excellent! How did you find coming to Teesside for a few days?

Rhys and Helga rolled out the welcome mat, showed me around the campus and gave me a crash course in using pXRF. And bingo, I was all set!.. until some unexpected hiccups…

Oh no! What happened?

The pXRF stopped working properly and had to be repaired, which muddles up all the project timelines. Disaster! (Okay, so it wasn’t that much of a disaster). But, with Helga’s supreme organisation and flexibility of everyone using the pXRF, things were quickly back on track better than ever!

Glad to hear it was sorted out! So… what did the pXRF do?

With pXRF, I could zap the bones with X-Rays and find out what kinds of elements are in the bones (and how much of them there is!).

What did this tell you?

I found that the real time-consuming part of pXRF was playing with all the numbers and figuring out what they might mean. My summer was spent making scatterplots and doing statistical tests to try and tease out patterns in the data that could be related to scurvy, or rickets, or any of the other diseases I was looking at.

Data, data, data! What did you find out?

The patterns remained elusive (science!), but the search was fun! I looked at elemental ratios potentially related to cribra orbitalia, neoplastic disease, rickets, scurvy, syphilis, and pathological new bone formation. Unfortunately, elemental ratios were more closely related to post-burial processes, but examining larger sample sizes of each pathology could shed light on new information.

I see! Did you find out anything else?

Actually, I found out how useful the pXRF is! This work couldn’t have been done without pXRF because it allows rapid and non-destructive analysis (can’t go chopping up and grinding down archaeological collections willy-nilly!).

Awesome, go Team pXRF!

 

It’s absolutely fantastic to see students get their work get published, it’s such a great boon for PhD application process. I’m sure you’ll join us in wishing Naomi all the best in her bright academic future, we look forward to seeing what comes next!

TUBA