Category Archives: terra sig


Overall, the results were very good. There were five of us total, and everyone was happy with their pots. It was cool seeing everyone else’s forms. Some small, some large, some handbuilt from textured slabs wrapped into vases.

Unlike glazeware, after the firing the work has only started. We had to unwrap and the scour the pots to remove the ash and residue from firing. Today I began the process of waxing the burnished / terra sig’ed ones. Kinda like waxing my Dad’s van as a kid, only smaller.

Here is today’s effort, after mowing the yard in between raindrops and other weekend chores.

Photo montage

So this weekend I finally got around to taking pictures of my past and present work so you can see what the heck I’m talking about. I’m also going to backpost some of these into my previous posts for future newcomers.

Naked raku

These are from my one and only attempt at this. It was in a class at the art center and there wasn’t much leeway for experimentation. I like the overall effect, and I can see the potential there, but I’d like to try some different masking slips to see if I can get a larger crackle pattern.

Saggar firing

These are more recent, using the tin-foil saggar method described in Alternative Kilns and Firing Techniques. Great book, full of ideas. It covers raku, sagger, pit and barrel firing, with dozens of variations.

Works awaiting the flames….

These are a few of the pieces I have waiting to be saggar fired next Saturday. The orange is the first attempted application of red terra sig. The shinier ones have had white t.s. applied and been polished. This is the last look at them before they’re wrapped in aluminum foil in a cocoon of plant materials and metal salts.

First attempts with terra sig

Short for ‘terra sigillata‘ the Romans used it to cover their pots. It’s a clay slip made of only the finest clay particles. Brushed on in several thin coats, it almost shines itself. It’s very cool stuff!

For my first attempt, I just used some old dried out white stoneware clay scrap I had. Searching around on the internet and the clayart archives, I’d found several recipes, the most definitive being Vince Pitelka’s procedure. Not having all the equipment and chemicals needed, and just wanting to do a rough first draft, I found this article on Ceramic Arts Daily by Joan Carcia.
(Ceramic Arts Daily is a nice site, and free to join)

Being a rough test, I found I had about 2lbs of dried clay, so I used about a gallon of water, and a tablespoon ful of TSP that I found at the local building/home store.

After settling and siphoning, I poured it into a biqued bowl I hadn’t gotten around to glazing yet to evaporate/absorb some of the water off. (Tip: soak the bisqe in some water first to get the pores of the clay ‘siphoning’ quicker)

I’m finding the white sig is working very well. Outstanding actually, for the sloppy way I followed the directions. I now have a larger batch made with red clay scraps settling, and will need evaporating. I just tried using some I siponed of the top yesterday and it’s just too thin. I rubs right off when I try and polish it.

This time around, I was looking for the quick and dirty way, since I wanted to try it on some pots headed to a saggar firing in a couple weeks and I had to get them bisqued. My next attempts will be following Vince’s process, and I can’t wait to have some super sig to experiment with!