In the ancient world, if you wanted to sign something you used a seal. They came in various shapes and sizes – stamps, seals, signet rings – but the general idea was always the same: you had a small object that you could press into clay or wax to mark it with a design unique to you – just like a signature. This could be used in various ways. In the Near East, for example, legal decisions or transactions might be recorded on a tablet, and then all the witnesses would press their seals into the clay next to their names. In other cases it could function as an official lock – a door or container-lid could have a blob of clay pressed over the join and this would be marked with an official’s seal. If the clay was broken – or if it had been replaced with one without the seal – then people would know it had been tampered with. Here’s one of the most famous examples of this: the unbroken clay seal on the tomb of Tutankhamun, photographed before it was opened in 1922.
Using seals is often a precursor to the development of full-fledged writing. The designs on them are often significant, and over time can develop complex languages of symbolism and iconography. Some designs might be used with similar meaning on multiple seals. It can be a small step from a stylised design that represents an idea and can be used in various ways to a pictographic writing system. In many cases it can be difficult to decide whether something is a mere picture or an early form of writing.
In the ancient world there were two main kinds of seal: stamp seals and cylinder seals. The first kind are exactly what the name suggests: carved stamps that you would press down into the clay or wax. Here’s a Minoan example, showing bull-leaping.
In the Near East and Mesopotamia, however, the more common type was the cylinder seal. These were small cylinders that could be rolled across a surface to create a continuous impression. Here’s an example from the city of Mari in the third millennium BC.
Recently we’ve been trying our hands at a bit of experimental archaeology by making our own clay tablets. When I made my cuneiform tablets, I had to copy from ancient examples that didn’t have seal impressions, because I had no way of replicating them. Since then I thought about it, and decided to have a go at making my own cylinder seal.
I should say, this is more for fun than real experimental archaeology. Making a real seal was an incredibly skilled task that involved carving minute, highly detailed designs into hard stone, ivory or metal. I simply don’t have the skills or tools to attempt that. Instead I decided to use clay. I ended up using two techniques in my experiments and I’ll present both here. Both have tricky aspects and easier ones. The second is faster and gives better results, but is also more demanding in terms of carving skills. See which works for you!
I’ll be trying to replicate two designs taken from real cylinder seals found in Ugarit and including alphabetic cuneiform inscriptions (if you want to add your own cuneiform, have a look at my blog articles on how to do it).
I thought the easiest way to produce the design would be to begin by creating it flat and then to transfer it on to the cylinder. So I ended up effectively carrying out the sealing process in reverse. First you need to create a flat rectangle of clay and to carve your design into it. You should make it a mirror-image of what you want the final impression to look like – as you can see, I forgot to do that with mine! You should also make the carving as bold, deep and smooth as you can. Once you’ve finished, leave this to dry fully.
We use this as a kind of stamp seal to get a reverse impression. Make another rectangle of clay and press the dried one firmly down on top of it. All being well, you should have transferred your design on to that, but now it’s reversed and raised above the background. Now leave that to dry too.
The last thing you need to do is to make the cylinder itself. You can use a strip of paper or bit of string to measure the length of your design and then curl it round to find what diameter your cylinder needs to have. Once you’ve rolled the clay to the right size and trimmed off the ends, you should roll it firmly over the dried impression. This is the hardest bit to do – you need to press down firmly on the cylinder so the design transfers, but without squashing it or smudging the bits you’ve already done. I found it worked best to hold it by the edges.
If you do it right, you should end up with the design wrapped round the cylinder, hopefully clear and deep enough to leave a good impression. Once it’s fully dry you can test it out. Air-drying clay will re-soften a little as you roll it because it picks up moisture from the wet clay it touches, so once you’re happy with it, I’d recommend using some kind of sealant or varnish to stop it blurring away. You can buy acrylic varnish from craft or model shops – use matt or satin, not gloss.
I found that while this method worked, the end result was a bit blurry and indistinct and lost a lot of the finer detail, simply due to the repeated impressions and the difficulty of rolling the soft cylinder over the design.
Being a bit dissatisfied with the results from the first method, I tried the more direct route: carving the design directly into a wet clay cylinder using a skewer. The tricky bit is that you’re now carving into a curved surface, which means you can’t see what you’re doing all at once and you still need to be careful not to distort or smudge it. But at least you don’t need to press down and can be certain that your design will be deep and sharp enough to give a good impression.
Picking the right design obviously helps a lot here. I’d recommend going with something fairly simple to start off with. When you’ve chosen your design, I’d recommend practising a few times on flat clay first. If you’ve already tried the first method, you’ll have a good idea what idea your cylinder and design need to be to fit properly. Once you’ve got your design all around the cylinder, just leave it to dry, varnish it like we did in the first method, and roll it across your wet clay or wax to leave your mark! Depending on the colour of your clay, you might also want to give it a light wash of acrylic paint to make it look a bit more authentic, like I did. Just be careful not to clog your carved design with varnish and paint!
I hope this works for you and you have fun! If you give it a try, we’d love to see what you come up with. Send us a picture of your results via Twitter (@crewsproject) or by email at crews[at]classics.cam.ac.uk.
Philip Boyes ~ Research Associate, Crews Project