The paper discusses the use of in-situ micro-Raman spectroscopy for the identification of calomel – a mercury (I) chloride mineral with formula Hg2Cl2 – as a white pigment in a 15th-century English manuscript and a late 16th-century portrait miniature by renowned limner Isaac Oliver, both belonging to the Fitzwilliam Museum in Cambridge, UK.
Although mercury chloride compounds have been employed for centuries in different fields including medicine, electrochemistry and cosmetics, the deliberate use of calomel as a pigment has been identified only recently within a few 17th-century South American objects. The present research, however, attests the first-ever verified presence of calomel within the original painting palette of two Western European works of art, predating its documented use in South America.
With ever-increasing possibilities to undertake non-invasive analyses of museum objects, it is quite possible that in the near future, calomel will no longer be considered an unusual pigment but rather will take its place as an integral part of the palette used by artists in different times and places.
The research behind this paper has been financially supported by the Cambridge Humanities Research Grants scheme, the Zeno Karl Schindler Foundation and a Short Term Mobility grant from the Italian National Research Council (CNR).
Archaeologists are increasingly under pressure to demonstrate that their work has impact beyond the discipline. This has prompted some archaeologists — and in particular, environmental archaeologists and palaeoecologists — to argue that an understanding of past environmental changes is essential to model future outcomes in areas such as climate change, land cover change, soil health and food security. However, few archaeological studies have explored how to put research results into practice.
Film showing the historic intensive agricultural system at Engaruka, Tanzania.
The EU-funded Archaeology of Agricultural Resilience in Eastern Africa (AAREA) project ran from 2014–2018 with the aim of looking at the long-term sustainability of two east African agricultural systems (Engaruka in Tanzania and Konso in Ethiopia). This was undertaken through a combination of archaeological, geoarchaeological, archaeobotanical and modelling techniques with the aim of providing a frank and realistic appraisal of the role archaeology can play in sustainability debates worldwide. The findings on the applicability of archaeological research were published through the generous funding from the NHSF Gold Open Access grant in Internet Archaeology in the article ‘Archaeology has no relevance’.
Admittedly, the title of the article might seem to imply our findings indicated that archaeology doesn’t have a role to play in the global conversation about sustainability, whilst in fact, the insights we gained showed that it was far more complicated than this. Archaeological results were not particularly relevant to policy-makers and NGOs in their raw state, or even in the form of a written-up scientific article, but the insights gained were of interest. In order to progress from, “Oh, that’s interesting” to the point where the insights can be used, a different way of working is needed. A way that is transdisciplinary and requires the ‘flow of knowledge’ to go in every direction, this may ultimately produce changes in the way we work, the methods we use, and the questions we ask. Enacting this way of working was beyond the limits of the AAREA project, but since the publication of ‘Archaeology has no relevance’ a new project, SOIL-SAFE, has been funded by the Global Challenges Research Fund through the Arts and Humanities Research Council to allow us to develop this idea.
Policy brief exploring the potential role of sediment traps can play in soil conservation practices.
Using one of the original case study areas (Konso, Ethiopia), SOIL-SAFE will build on the relationships created during the AAREA project. It will bring together those working in archaeology, ethnobotany, development studies, NGOs and those who live and work in the landscape to co-create a method with archaeological insights embedded from the beginning. Knowing how an agricultural system was built and operated over time is clearly relevant to an understanding of its current sustainability, but discussions of future sustainability must include everyone that is invested in this future. As archaeologists we can tell people what happened in the past, but the relevance of this information can only be determined through open conservation with the people that may choose to apply it.
The paper ‘Archaeology has no relevance’ is co-authored by Suzi Richer, formerly with National Trust, and Daryl Stump and Rob Marchant of the University of York.
On Monday 9th March a group of primary school teachers spent a day working with museum educators and research scientists from the Fitzwilliam Museum and Hamilton Kerr Institute (HKI) to explore different approaches to looking at museum objects and images.
This is the last blog of our British Science Week series and was written by Kate Noble, Paola Ricciardi and Rosanna Evans, with many thanks to Spike Bucklow and to the eight enthusiastic teachers who spent a day at the museum.
Background to the Project
The workshop formed part of the ‘Ways of Seeing’ research project, which aims to stimulate public interest in – and engagement with – the materials and processes involved in the making of objects in museum collections, by bringing together research on the development of visual literacy, non-invasive analytical protocols, visual perception and artists’ techniques. The project was designed with reference to a report, published by the Wellcome Trust in 2014, which identified the need to make science fun and exciting and to support pupils to develop better enquiry skills. It also addresses the need for more high-quality subject-specialist Continuing Professional Development opportunities for primary school teachers in both Science and Art. The teachers’ workshop provided the opportunity to test ideas for a museum-based session for KS2 schoolchildren, aimed at supporting the development of analytical skills essential to both artistic and scientific investigation.
Ways of Seeing builds on the success of Inspire, an exhibition of children’s art made in response to a 15th century panel painting of Cupid and Psyche by Florentine artist Jacopo del Sellaio. An extraordinary 3800 children took part in the project and a selection of their work is currently on display alongside the original painting at the Fitzwilliam Museum. While local schools and teachers were studying the painting in school, the museum’s own heritage scientists and painting conservators were asked to undertake their own technical and scientific research on the panel. Findings from these analyses are included in the exhibition, most prominently as part of a new AR app that invites visitors to look ‘beyond the surface’ at the materials and processes of the Renaissance artist.
Working with the teachers
The session started with an in-depth exploration of Cupid and Psyche in the exhibition gallery, which included drawing, looking at and learning about the painting with museum educator Kate Noble. The teachers also had a chance to look at infrared and X-ray images of the painting, trying to interpret their meaning and brainstorming about the scientific topics that could be discussed with children based on these images.
Spike Bucklow, Director of Research at the HKI, gave us a tour of his Sharpening Perceptions exhibition, which features original paintings alongside historically accurate copies produced by the HKI’s post-graduate students as part of their training in paintings conservation. From the nature and geographic origin of pigments and paint binders – a range of both organic and inorganic, natural and synthetic compounds – to the importance of colour temperature and direction for the light used to illuminate a painting, there was a lot more science to talk about than many of us had thought possible!
We also spent time in the Museum’s Analytical Lab, where Senior Research Scientist Paola Ricciardi talked about a range of non-invasive imaging and analytical methods, which she uses to investigate colours and pigments. Back in the Education Studio, Paola gave a practical demonstration of some of these methods and got an amazed ‘ooooohhh’ from the whole group when demonstrating the three-dimensional texture of paint on a tiny portrait miniature – no more than 4 cm across!
These conversations then fed into a practical session led by museum educator Rosanna Evans, where the teachers worked in small groups, experimenting with paint-making as a form of scientific enquiry. They ground locally sourced earths to make a yellow pigment and tested mixtures made with different paint media (water, egg white and egg yolk), applying them over a range of different surfaces. The best – or, for someone, the worst – part of this process was the screeching sound made by the coarse earth being ground with a glass muller – who would have thought that particle size could ‘speak’ to us so loud and… clear?
The day finished with a stimulating discussion about how these activities and approaches might support the teaching of art and science in primary schools.
The day couldn’t have gone better. The lively conversations we had with the teachers and their enthusiastic feedback confirms what we thought all along: truly collaborative cross-disciplinary research has immense potential to be the starting point for developing user-led projects with practitioners, and to explore different pathways to impact for object-based research. In the words of one of the teachers, “I don’t think there is any part of the curriculum that you couldn’t bring into this!” We are now looking forward to inviting the teachers back to the museum with their classes in the Summer term to take part in our new Ways of Seeing workshops for KS2 children.
STORMLAMP is a research project that monitors and measures the impact of waves on the structural performance of lighthouses.
The project began in May 2016 and has focused on six lighthouses spread across the British Isles. These lighthouses were selected due to the particularly extreme wave environments that surround them and their unique structural elements or operational issues.
The STORMLAMP project is a great example of how engineering can benefit communities, trade and heritage. Historic rock-mounted lighthouses continue to play an essential role in the safe navigation around perilous reefs. However, their longevity is threatened by the battering of waves which may be set to increase with climate change. Virtual navigational aids such as GPS are fallible, and reliance on them can be disastrous. Mariners will continue to need lighthouses as these physical visual aids are strategically placed to assist navigation. The loss of any reef lighthouse will be incalculable in terms of safety, commerce and heritage.
This complex project requires a unique combination of skills available from three UK universities: University College London (UCL), University of Exeter and University of Plymouth.
University of Plymouth works on predicting extreme storm conditions for offshore rock lighthouses using long-term metoceanic data. Plymouth also carries out physical tests using scale models of lighthouses and uses Computational Fluid Dynamics modelling to identify how wave loading interacts with these rock structures. University of Exeter accesses the lighthouses for installing monitoring systems and performing modal analysis in order to identify the structural characteristics of the lighthouses. Finally, UCL uses the data produced from the other two universities to carry out detailed structural analysis to assess how resilient the lighthouses are under extreme wave impacts.
One of the lighthouses STORMLAMP is investigating is Wolf Rock, which lies about 8 miles from Land’s End. The tower is built upon a rocky pinnacle which is completely obscured at high tide and was selected for long-term monitoring by STORMLAMP due to the unbroken Atlantic waves it encounters. It’s one of the larger towers in the project at 41m and was built in 1869. As with many of the lighthouses access is via helicopter, landing on the helideck at the top of the tower. Modal testing took place in 18 July 2016 and James Bassitt, based at University of Exeter took some fantastic footage from the helicopter flight to Wolf Rock.
As the four-year project comes to a close, a final workshop is planned for May 2020 to showcase the STORMLAMP research to a wider audience. The workshop will involve presentations on lighthouse research and relevant areas from academics, heritage professionals and industry stakeholders, as well as discussions on future directions for related research.
To find out more about the project and the lighthouses STORMLAMP has been working with, visit the website. There are plenty more pictures of the team in action and details of our partners and of course the lighthouses themselves.
The next blog in our British Science Week 2020 series come from MSDS Marine, a Marine and Coastal Contractor specialising in the management, execution and support of archaeological projects in the marine environment.
The Rooswijk was a Dutch East India Company vessel which sank on the treacherous Goodwin Sands, off Kent, in January 1740. The ship was outward-bound for Batavia (modern-day Jakarta) with trade goods. The site is now protected by the Protection of Wrecks Act 1973. The ship’s remains are owned by the Dutch Government; however, the UK government is responsible for managing shipwrecks in British waters, therefore both countries work closely together to manage and protect the wreck site.
A two-year archaeological excavation project was undertaken between 2017 and 2018 due to the site being at high risk of loss through environmental changes and unauthorised diving. Wrecks such as the Rooswijk are part of the shared cultural maritime heritage across Europe and it’s important that cultural heritage agencies are able to work together to ensure that sites like this are protected, researched, understood and appreciated by all. The project involves an international team led by The Cultural Heritage Agency of the Netherlands (RCE) in partnership with Historic England. MSDS Marine are the UK Project Managers for the project.
A number of stacks of coins were found during the excavation. Some of these were carefully separated by the conservators from the Investigative Science Team at Historic England (Figure 2). Some could not be separated.
A number of stacks were then sent to the μ-VIS X-ray Imaging Centre (www.muvis.org) at the University of Southampton to be micro-CT scanned. X-ray micro-Computed Tomography (µ-CT) scanning is a volumetric scanning technique, which enables us to virtually cut open materials to look inside with micrometre spatial resolution, while preserving the condition of the object we are scanning. During the scan, the object is rotated 360 degrees as thousands of 2D X-ray projection images are acquired. These 2D images are then reconstructed into a three-dimensional volume, which is made up of cubic pixels with intensities related to the amount of x-ray energy absorbed at that point.
We used the custom walk-in scanner (the Hutch) at the µ-VIS X-ray Imaging Centre to scan the concreted coins, which were stacked in sealed tubes to prevent excessive drying during the scanning process (Figure 3).
The digital reconstructed volumes were then sent to MSDS Marine, where myVGL software (Volume Graphics GmbH, Germany) was used to manipulate the volume data, so that the individual faces inside the stacks could be seen (Figure 4). These coin faces have not been seen since they were packed into chests for the voyage almost 280 years ago.
The coin face slice images will be sent to Jan Pelsdonk, the projects numismatist, for identification and will contribute to the understanding of the wreck.
The application of scientific techniques like CT scanning and digital model processing have contributed hugely to the understanding of underwater heritage, and continue to offer new and exciting ways of investigating these important cultural sites.
Author: Natalie Brown Senior Conservation Manger – Engagement
The purpose of the Collection Care Department at The National Archives is to ensure access to our collection through its long-term preservation and display. Through established and innovative programmes of environmental management, conservation treatment, and research initiatives we aim to prolong the life of our collection for future generations and enhance the artefactual value of archival collections beyond what is written on the page. As a department crouched in an Independent Research Organisation (IRO) we are able to co-create applied and interpretive heritage science projects that enable us to investigate the material composition and physical state of the collection, study how art materials were used throughout history, model how materials will degrade, and address changing conservation practices. Below are two projects highlighting how we do this in practice.
The aim of ArcHives is to use wax as a bimolecular archive to inform upon the geographic origin of beeswax (and bees); the changing diversity of the hive microbiome in modern; and historical beeswax and the DNA of individuals associated with the production of the legal documents trapped in kneaded wax. The National Archives holds over 250,000 seals dating from the 11th to the 20th Century and this project will allow us to explore our wax seal collection on a biomolecular level. We hope to gain knowledge around the material composition of wax seals in our collection which will allow for a deeper understanding of the physical and chemical processes responsible for their ageing and degradation. The four-year project is led by an international cross-disciplinary team of molecular biologists, palaeoproteomicists, heritage scientists, historians and chemists. Lora Angelova PhD, the Head of Conservation: Research and Engagement, is an advisor on this project.
AI for DigiLab
AI for DigiLab aims to combine artificial intelligence and advanced imaging techniques to analyse historic map collections. The project is a collaboration between The National Archives, Nottingham Trent University – ISAAC group, Yale, Getty GCI, and University of Southern Maine- Osher Map Library. The National Archives holds around six million maps ranging from the 14th to 20th Century, some of which are hand-drawn and colourfully painted. Image techniques, such as x-ray fluorescence scanning or multispectral imaging, are useful to investigate the materials, such as pigments, inks and dyes, used by the mapmakers. In the project, algorithms will be used to analyse the large datasets produced from these imaging techniques to determine the materials present in the maps. We hope that by applying big data analysis to international historic map collections we can shed light on maps production context, the trade of the materials, and possible influences between the metropolis, the colonies and across media. Lucia Pereira-Pardo PhD, Senior Conservation Scientist is a co-investigator on this project.
The latest blog post in our British Science Week 2020 series is written by Clara Gonzalez, a post graduate student studying for an MLitt in Technical Art History at the University of Glasgow. She is currently doing a work placement with the Conservation Department of the National Galleries of Scotland.
The National Galleries of Scotland (NGS) and the Technical Art History Group, Glasgow University (TAHG) are working together on a systematic technical study of Christ Teacheth Humility by Robert Scott Lauder (1803-1869).
In 1847, Lauder submitted this painting to a competition organised to provide works of art for the Houses of Parliament. Lauder did not win, but the painting gained him public recognition. In 1849 it was acquired by NGS, becoming part of the early foundation of the collection.
The vivid palette used in the painting reveals Lauder’s interest in the effects of colour, inspired by Venetian 16th century painters such as Titian. At the time Lauder was working, traditional pigments were still in use, and artists experimented with pigments made from newly discovered compounds which were also commercially available.
A well-established analytical method for the technical examination of paintings (specifically the identification of inorganic components of artists’ materials) is X-ray fluorescence (XRF). XRF is a non-destructive, non-invasive analytical tool. The TAHG XRF analyser is a portable, handheld Niton XL3t. This portability is particularly suitable for examination of this work due to its dimensions (2.5 x 3.7m) and offsite location in the gallery store. Using XRF, we will characterise inorganic elements present. In combination with other techniques (such as paint sampling) this analysis will be used to build a holistic picture of materials used, including pigments, and to gain an understanding of Lauder’s material choices for this painting, the most ambitious project of his career.
The next blog post in our British Science Week 2020 series is written by Elizabeth Stephens from Historic England.
Key facts about the Geospatial Survey Technician Apprenticeship –
A new apprenticeship standard approved for delivery in February 2018
Level 3 – this is equivalent to an A level
Based within the Construction route
Typically lasts 2 years
Time split with 80% working within a company and 20% off site training
My experience as an apprentice
I am now 16 months into my Geospatial Survey Technician Apprenticeship at Historic England. A lot has happened in that time. Projects undertaken have included coins, caves, churches and castles, all very different and all very interesting.
I am employed by Historic England in the Geospatial Survey team. It’s a great place to work and the sites and objects I get to see are amazing. The support I receive at Historic England is excellent, there’s always someone to talk to, explain a piece of equipment or give advice.
My role at Historic England in one sentence
Using a range of equipment and software including different scanners and photogrammetry to survey building and objects, often generating 3D models that can be used to aid conservation work, monitor the structure, record, or as a learning tool.
Leeds College of Building
I spend around 20% of my time at Leeds College of Building where I have been learning lots. This year’s units have included Topographic Surveying and Geographical Information Systems. The units this year have been really interesting and very relevant. The first year was more background theory but this year has been more connected to what I do at work and has a bigger emphasis on the practical application.
I have been lucky enough to be part of the first group of colleagues at Historic England to undergo training and receive our PfCO (Permission for Commercial Operations). I am now able to fly a drone to capture images of different sites that are used to complete surveys.
Photogrammetry and laser scanning
Within my work at Historic England we often carry out laser scanning at sites to capture the shape and condition of a building or object. The laser scans are joined together when back in the office and produce a 3D model of the building or object. We use a range of scanners including mobile, hand held systems.
Photogrammetry is also used which involves taking many overlapping images that are then processed to produce a 3D model.
These methods can be combined into a ‘reality capture’ model combining the superior images from the photogrammetry and the geometry from the laser scanning. The laser scanning produces the framework that is then wrapped in the images.
Why apprenticeships are fantastic
Gain qualifications while earning
A chance to meet others within the industry for future contacts
Support and guidance from everyone in the organisation
Learning a wide range of transferable skills
Practical experience working within the sector
A chance to change career and learn a new skill set
This is the last blog post from Historic Environment Scotland in our current British Science Week 2020 series.
Written by Bonnie (Nicole Burton)
Since starting my Trainee position in August with Historic Environment Scotland, I have worked with the Digital Documentation team on various sites, ranging from Neolithic chambered cairns at Kilmartin Glen to Iron Age Brochs at the Isles of Lewis.
These projects were undertaken as part of the Rae Project, involving both the Digital Documentation and Digital Innovation team at the Engine Shed. The focus of the Rae Project is to digitally record all historic sites in Historic Environment Scotland’s care across Scotland, as well as their large array of collection items. The aim of this project is to have a full database for sites that are vulnerable or at-risk, using the datasets for management and monitoring.
The largest project I have been involved with was at Kilmartin Glen in August. The teams spent two weeks digitally documenting 15 sites and 30 collections items. Kilmartin Glen is located in Argyll and Bute, western Scotland and is enriched with prehistoric monuments and historical sites.
The documented sites range from chambered cairns, historic buildings, rock art, stone circles and stone artefacts. After the initial documentation had taken place the processing of the data had to be carried out using a wide range of software packages to create accurate 3D models that can be shared with the public [https://sketchfab.com/3d-models/cairnbaan-west-kilmartin-glen-7b63521779c440c19bd7079ba2d5842f].
Terrestrial laser scanning
Laser scanning is a straight forward process: the instrument has a rotating laser beam that reflects off a given surface, creating billions of points in 3D space representing the shape of a surface. Whilst scanning, multiple factors are needed to be taken into consideration, including the need for overlapping scans is to ensure a complete 3D model can be created, the terrain and environmental conditions. Our team uses a variety of laser scanners– some used for overview scans and others for the finer detail.
Photogrammetry is a technique of using a camera to take overlapping photographs ensuring all areas of the subject has been captured to create a 3D model. While simple in theory, the better the pictures, the better the model, so we make sure to use a colour checker and a good lens.
Heritage in Scotland is becoming more and more at risk due to increased flooding and the changing climate. The work our team is doing not only at Kilmartin Glen but on other sites like Skara Brae is aiding in the management and monitoring of significant cultural heritage.
If you use twitter and would like to keep up to date with our projects, then follow the #Raeproject and @Burton1495
The next post in our British Science Week 2020 series is about a project supported by funding from Historic Environment Scotland, a NHSF member.
Written by Cecily Spall, FAS Heritage
The Tarbat Discovery Centre, Portmahomack, opened in 1999 in the former medieval church of St Colman. It displays the results of 20 years of archaeological research excavation focussed around this important church. Along with National Museums Scotland, the Centre cares for the collection of burials, dating from the 7th to the 16th century, excavated from in and around the church building.
St Colman’s Church was built in the 12th century in the abandoned burial ground of an 8th-century Pictish monastery. Burials continued from the 13th to the 16th century. Over 80 medieval burials were excavated and include a small group of burials which were highly unusual, displaying burial rites never before seen. The central burial was that of an older man – ‘Chieftain A’ – who had died aged 46 to 59 years from a horrendous facial injury caused by a blade (Image 1). On his death he was interred in a large coffin which included four extra skulls set at his head (Image 2). About a generation later his grave was reopened and the body of a second man – ‘Chieftain B’ – was laid on top with the skulls now set around his head.
A Historic Environment Scotland funded programme of archaeological scientific analysis is now underway, designed to better understand these extraordinary burials. This includes radiocarbon dating and ‘Bayesian’ (statistical) modelling of the dating brackets to refine them. The results suggest that Chieftain A died between AD1290 and 1410 and Chieftain B between AD 1380 and 1450; three of the skulls buried with them died between AD1250 and 1400 and the fourth belonged to a Pictish monk who died between AD770 and 900. These extraordinary burials belong to the period when the clan system was becoming established and so represents an important part of understanding Highland heritage and the history of the community of Portmahomack.
Multi-isotope analysis measuring strontium and oxygen preserved in tooth enamel has also provided information on region of birth with Chieftain A having grown up on or around the Tarbatness peninsula, and Chieftain B growing up elsewhere, perhaps in the Western or Northern Isles, moving to Portmahomack later in life.
Computer-based reconstruction of the face of Chieftain B has been undertaken using European datasets to model his likely appearance (Image 3), work which was generously funded by the Society of Antiquaries of Scotland. Ancient DNA analysis is also underway at Harvard University and it is hoped that it will provide information on possible family connections between the burials, as well as likely skin tone, and eye and hair colour, and perhaps even his deeper shared ancestry.