How It Was Done
Producing Images of the Jamestown Reliquary and its Contents
The silver box brought to Micro Photonics by Jamestown Rediscovery begged the question: What is inside? The box, an important historic artifact, could not be opened without risk of damage to either the box itself or its contents.
To find an answer, we used X-Ray microCT imaging, as it allows researchers to see through objects with unprecedented clarity without damaging the item. X-Ray Computed Tomography (CT) imaging is a relatively new science, and it was not until 1972 that the first CT scanner was made by Godfrey N. Hounsfield. His invention changed the way we see the internal structure of the world around us. And the technology continues to evolve.
The silver box presented a perfect case to test the capabilities of X-Ray microCT imaging and how we might progress from scanning, to 3D imaging, and even to 3D modeling. But would the metal involved be too dense for X- Ray imaging?
Using our Bruker SkyScan 1173 microCT (link) system we turned on the X-Rays and took a first look through the box. The preview image was astonishing. We could see two metal pieces, possibly of lead or another dense metal (See Figure 1), and some hints of other materials. The scientists at Jamestown Rediscovery eventually determined that the metal pieces were an ampulla (a small flask to hold water, oil, or perfume).
While the preview image provided a useful 2D rendering we were now ready to fully scan the item and create the 3D images that truly make microCT imaging so unique. As the sample rotated thousands of images were taken and processed through advance imaging software. The output images revealed more details of the silver box and it contents. And it changed our understanding of the artifact we were handling.
The initial microCT scan revealed that there were bone fragments inside the box, along with the ampulla (Figure 2). Suddenly, were not just dealing with a simple silver box, but a reliquary!
David Givens and Michael Lavin from Jamestown Rediscovery knew they wanted to continue with a higher energy microCT scan, which was not available in Micro Photonics’s lab at the time. They took reliquary to the Cornell Imaging Facility at the Cornell University Institute of Biotechnology. There they acquired additional images that helped to further distinguish the bone fragments. David and Michael then brought those scan results back to Micro Photonics’ lab to extract further information from the images. We used Simpleware’s ScanIP software to enhance and segment out each bone fragment, and create virtual 3D models (Figure 3) from the data gathered at Cornell. Saving the enhanced images allowed us to load them in our Bruker CTVox software to create realistic, semitransparent 3D images (Figure 4).
The successful creation of the 3D images and computer models of the reliquary and its contents led us to the next tools of our trade: a 3D video and 3D printing. The 3D video we created essentially brings the artifacts to life on screen – offering a dynamic view that can be rotated and manipulated. It also allows a close and detailed look at features of the objects, providing opportunity for further study. For instance, you can clearly see the shape and texture of the bone fragments, as well as their relative sizes, and anticipate what they might look like physically (See video below).
The last step in our contribution to this project was to create a tangible representation of the objects hidden inside the Jamestown reliquary.
Click Here to learn more about how the 3D models were printed.
Our deepest thanks to David Givens and Michael Lavin and the teams at Jamestown Rediscovery and Preservation Virginia for bringing this fascinating project and historic puzzle to us at Micro Photonics. We are grateful to have been involved in the investigation process and to have witnessed history unfold firsthand. Special thanks, too, to the Cornell Imaging Facility for generously sharing use of their images. The images and models shown here would not have been possible without these collaborations.
If you are interested in learning more about this great project and recent discoveries at historic Jamestown, we encourage you to visit the Jamestown Rediscovery website.