What is Nerikomi?

Neri what? Neri-komi, not to be confused with Neriage is a Japanese word which designates pattern techniques with colored clay in handbuilding. The prefix "Neri" means to mix or to blend, and the suffix "komi" means to press. So mixing and pressing clays together. The suffix "age" means turn, so Neriage means the mixing of colored clays on the potter's wheel.

Here you can see a Neriage piece by artist Ogata Kamio. We can observe a spiral movement in the colors, characteristic of the work of colored clays on the potter's wheel. The artist then engraved to reveal the colors of the lower layers and thus create this vessel.

Ogata Kamio, Ridged Neriage (marbleized) pot (2017)

''When asked to explain how I make my pieces, I say it's a bit like painting with plasticine. I start with a large blank slab, and I apply the patterns in successive layers, a bit like building an image in screen printing or paper collage.'' -Ogata Kamio

The steps:

1: the coloring clays: To obtain the colors, I blend pigments and oxides specifically designed for ceramics which develop with a firing at 1200 degrees celsius. Pigments are already fired recipes of different oxides: The color we see in the jar is what we will see on the piece in the end. (Note however that diluted in clay, pale colors often become invisible and are revealed after firing. See below how the vivid yellow becomes dull mixed in clay, it will become bright again after it’s fired.) Oxides are powdered minerals which sometimes change color after cooking. For example, cobalt oxide is a pale lilac that turns deep blue when cooked, and manganese oxide, naturally brown, can give hues of purple, red and pink when mixed with an alkaline. Pigments and oxides must be handled with great care as they are highly toxic.

1: Pesée de pigments et mouillage. 2: Application de la pâte colorée. 3: rouler. 4:pétrir

2: Color Charts: After coloring clay, I mix some together to create my unique palette. As in painting, you can't mix equal parts of yellow and blue to get green. The pigments all have different power and it could be that we need only 10% red and 90% yellow to get orange. To know in what percentages do my blends, I make swatches with triaxial method with clay samples. Once the samples are fired I see the final color and I can reproduce them in larger quantities. This work is laborious, but when it is well noted and tidy, I can refer to it in the future. It is not to be redone every time, but I still advise to fire test samples of every time you get new bags of pigments as the availability of raw materials in the industry can change therefore the outcome can also change.

Image 1 : Préparation de petites quantité de barbotines colorées: l’état liquide aide à mélanger plus rapidement. Image 2: les échantillons de mélanges sèchent sur une plaque de plâtre. Image 3: pastilles de mélanges par la méthode triaxiale émaillés à la moitié, pour voir la différent de teinte avec ou sans la glaçure. Image 4: Boules d’argiles pétries selon les recettes découvertes dans la recherche de nuances.

2: blocks and canes: Before making the large patterned slabs in which I will cut pieces to make objects, I make blocks of patterns that I can then cut slices out. I usually do enough to make complete collection (around 20 big slabs). It is at this stage that I will make the gradients, the marbles, the checkered patterns, etc. I will write posts on these different techniques to explain them in more depth eventually

Image 1: Damier. Image 2: Marbre. Image 3: Dégradé de bleu en couches. Image 4: dégradé de jaune fondu.

With a slab roller (like a dough sheeter but for clay) I will make several large slabs that I will display on a large work surface. With about 6 large slabs I will be able to make several objects, between 50 and 80 more or less. After some preparation steps of the slabs I can now start to build the images. A bit like we would work in screen printing, I apply the colors one at a time on all surfaces. I usually start by adding large colored clay pieces that will be in the background, and continue the layers to the smallest details that will be in the foreground. The patterns are shaped and cut out like a collage of paper. Before each new color, the previously joined patterns are integrated into the soft slab using a roller. I put a damp cloth between the plate and the roller to control the excess surface slip and keep the work in progress very damp, essential for the layers to stick well together. Finishing the decors on 6 large slabs takes at least 4 days, sometimes more. When it's finished the slabs are stored for a few days. The resting time is essential before starting making objects so that all add ons equalize their humidity level. Neglecting this step will create tensions between the layers which will make the pieces crack

4: After the resting time, the large slabs will be cut and then I do all the normal stages of pottery production with slabs.

5: Cleaning and sanding: The colors mix on the surface when the colored clays are wet. To get clean and sharp color I will need to remove the dirty layer on the entire surface of the objects. Dry sanding is very harmful to the health, so I do a first cleaning with a sponge on almost dry greenwares to remove the surface layer. Then the pieces finish drying and I do a light sanding to ensure that the colors will be sharp and pure.

6: Sanding on bisque ware: When the pieces are dry it is difficult to see very well what going on and sometimes after the bisque firing I see spots that I had missed, and I can correct it at this stage. The bisque wares are immersed in water and wet sanding is done with water-resistant sandpaper or diamond polishing pads.

7: Then I finish the pieces in the same way as the other ceramic techniques.

I hope my explanations have succeeded to demystify my work a little. In my next post I will introduce you to the endless possibilities possible with nerikomi with examples of ceramic artists who use this technique in their work.