,
11 tweets,
4 min read
Read on Twitter
One of the star objects of the newly opened Islamic World gallery in the British Museum is this ewer from Herat, with beautiful birds surrounding the collar. With X-ray CT scanning, Museum scientists were able to determine how the birds were made. #PhotonFriday @britishmuseum
The ewer was scanned in the British Museum's X-ray Imaging laboratory, located 4 floors underneath the Museum. On the right of this picture is the X-ray tube. The X-rays come out from just behind the brass square, pass through the ewer, and make an image on a digital detector 
The X-rays can be very high in energy (max. 450 keV for fellow photon-aholics), very helpful for looking through brass/silver objects such as this
By rotating the ewer whilst taking images, we can see the inside from all angles, allowing us to make a full 3D volume of the ewer. Since the ewer is 40cm tall, I scanned it in two halves, top and bottom, then stitched the two halves together to give the result in the first tweet
In these X-ray images, we can see the silver inlaid design (it appears brighter because silver is denser than brass, and so it absorbs more X-rays), and various solder attachments. But what about the bird heads?
To answer this question, we can go through the 3D picture of the ewer slice-by-slice. On the right hand side here, you can see that the bird head on the collar is a white outline, continuous with the body of the vessel (as an aside, the handle is completely solid)
The bird heads were made by hammering them outwards from the inside of the vessel! They were not made separately and stuck on, as originally thought. It is clear that incredible artistry and skill was needed to make this ewer.
Here is a nice close up of the birds (thought to be parakeets or pheasants), showing the intricate decoration and silver inlays. You should most definitely go and see this piece in its wonderful display case in the gallery, it's a real beauty.
As another aside, I also imaged the Blacas ewer (from Mosul) which is displayed in the same case as the Herat ewer. The BM photographers took a great dramatic photo of the work taking place (I really feel they captured my best side)
(I am compelled to add that I do not take X-rays with the exposure room door open, for fellow X-ray scientists!)
I went to visit the ewer in the gallery last night :)
