Aršama Seals of the Achaemenid Empire

A collection of 2,500-year-old clay impressions (also known as letter-bulla) bearing the seal of Aršāma, a Persian prince and regional governor of the Achaemenid Empire, is the earliest group of objects to be recorded by ARCHiOx. The impression was made by an intricately carved tool, rolled over the surface of seven small unfired clay pieces – just over four centimetres in width.

Detail from the 3D model of Sigill. Aram. V. © ARCHiOx

As the clay is unfired, and in some cases the seals are held together by a string used to attach them to the letter they accompanied, these artefacts are extremely fragile. They are therefore, both difficult to handle but of great importance as objects for study. Recording them is critical to ensure their preservation. Detailed records of all clay seals and a fragmented letter were made using both the Lucida 3D Scanner and the Selene Photometric Stereo System.. The data can now be studied in depth and the seals recreated as facsimiles for exhibition display

A further part of the project involved recreating the carved cylinder used to make the original impression. Working back from the design captured by the recordings, the image was inverted and printed in 2.5D using Factum’s elevated printing technology developed by Canon Production Printing (previously Océ – A Canon Company). The elevated print was then fixed onto a cylinder and rolled across a plasticine surface to create designs incredibly similar to those found on the original.

Every tiny detail of the impression, historic repair and even the fingerprints of the maker are clearly visible. These features can be explored using a 3D viewer within GIS software. Moving over the surface of the recording is similar to flying over the surface of a desert landscape, where each granular element becomes a geographical feature. This new method of recording represents an important advance in imaging for the purposes of preservation. The recordings of the seals will allow researchers to study originals in a way that has never before been possible.

John Barrett, Bodleian’s Senior Photographer and ARCHiOx Technical Lead for the Bodleian