Clay and gemstones

Eva (from czech minerals), who is also potter, sensed my interest in nature materials in combinations with clay and sugested if I would like to have some gemstones send to see what they do in fire. It seems I receive this box of gemstones just in right time, when working on couple of project with surface, which called for a gem on top. I tested some of those (and will still keep on testing) in fire. The results were different for each, some did not move, some explode, some fire out, some turn to glaze and some reacted by half melting. It also seems a little irony, that from those entire tests the two stones, who shown the best possibilities for my purpose can be found in my country. As I do not know much about gemstones I realized that only after already using them on my work and than researching information about them. So here they are moldavite and crystals forever bind with clay by fire.

Pottery for five senses - Exhibition in Kulturkeller Dobersberg

As a couple we work on tea setting for almost 8 years now and with each kiln our understanding of individual aspect of the way of tea is growing. Tea settings are pictures composed of many parts, which complement each other, support each other and together they compose balanced and functional unit. We strongly believe that art of tea pottery can bring alive all senses. It is not only visual experience. Sound of pouring water, crackling of charcoal pleases ear, the aroma of the tea pleases nose, tea pleases body and the touch of handmade object pleases hands.

Tea experience never overwhelms these senses, it talks in subtle way. In quiet surroundings of one or with a group of friends it is able to bring senses alive, the sense, which seems to be omitted these days.

• Often we hold thing, but rarely touch - and yet - standing close to a beautiful tree - one still feels urge to touch it. We use touch to express our strongest feelings, where words can never be enough, in sadness, in happiness, in love… We all know that hug or hand touch can say so much more, then we could ever be able compile in words. 
• Often we are aware of smell, but rarely of an aroma – and yet – when somebody brings flowers the first thing one does is to smell the aroma to catch it in nose for a moment. 
• Often our surroundings is full of sounds, we hear, but rarely listen – and yet – when walking in nature by the stream, who would not stop and listen for a while.
• Often we eat and drink, but rarely taste, rarely distinguishes the variety of tastes in our mouth. With each cup of tea we can. 

In a way of seeing and knowing through use the visual is first, but not last sense in which objects are appreciated.

Tea settings are definitely not a still life, they meant to be arranged, moved and experienced. By use they come alive, with the tea they change, acquire a patina, mature and in time (just the same as old person), they talk. Tea leaves are created from rain, soil, sun and hundred years old wisdom of farmers. Our tea ceramics than is from clay, fire and creative spirit of pottery workshop. With tea bowl in your hands everything comes together with your story and lives on.

More photos of photographer Michal Zajačik from our exibition EINKEHR ZUM TEE in Kulturkeller Dobersberg you can see here.

Do you like walnuts?

In the post Ash glazes in time of potter’s life I wrote about walnut shells ash waiting to be tested as a glaze and it seems, that the time has come.

Why we use ash for glaze? The answer is quite simple, it contains (in most cases) all oxides needed to produce glaze. It is much easier ingredients to obtain - to understand this statement consider the amount of work involved in turning silica stone into silica powder and burning for example rice straw, which has quit large amount silica in its ash. It is pure fun to see unravel what is nature hiding.

How to turn walnuts into walnut glaze?

Enjoy walnuts and enjoy A LOT of them....

 

Collect walnut shells...

Burn walnut shells... and then be surprised how small amount of ash you get from a large amount of walnut shell....

Add water and sieve all the ash through glaze sieve.... Let it stand and then pour some water out ... Glaze should be on yogurt thickness. Glaze and fire...

Here is walnut ash on porcelain... 

And here on stoneware...

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A glaze with a lot of potential, luckily, all our family likes walnuts a lot, so they have been notify to save all walnuts shell for a different use, then bio recycle.

Glaze excavated in your backyard

Clay glaze is kind of earthly topping for your work. The beauty of those is not only that they are everywhere (meaning all over the globe), but also they are quite easy to find, processed and used. Most of clay glazes will be based and colored by Iron (most common element (by mass) forming the planet Earth as a whole), so the regular colors of clay glaze will be browns and green. Sometimes you will get black, blue, yellow green and any number of colors depending on which oxides are present in your clay glaze. Now I just hear it - but most of them are boring brown. Than first of all there is never boring brown, but encase you are not those brown loving enthusiast (potters know that brown has about thousand shades) let me show you, what little fun with clay glaze can do.

This summer on our glaze classes we conducted small experiment as a process of understanding glaze behavior and clay glazes and as a kind of jumpstart test when you want to adjust your clay glaze. Notice how glaze change with the clay type

The base for our test was clay glaze found, when our friends builded home in Obřany. Here applied on technical porcelain by itself.

With above clay glaze we made test as follows:
Clay glaze Obřany 200 - calcium carbonate 40

Clay glaze Obřany 200 - calcium carbonate 40 - Titanium dioxide 20

Clay glaze Obřany 200 - calcium carbonate 40 - Titanium dioxide 20 - Soda feldspar (Ž55NaK60) 30

Clay glaze Obřany 200 - calcium carbonate 40 - Titanium dioxide 20 - Soda feldspar (Ž55NaK60) 30 - Cobalt carbonate 4

To see even more results we started second test as folow:

Clay glaze Obřany 200 - Ash glaze (mixed wood ash glaze) 60

Clay glaze Obřany 200 - Ash glaze (mixed wood ash glaze) 60 - Zinc oxide 30

Clay glaze Obřany 200 - Ash glaze (mixed wood ash glaze) 60 - Zinc oxide 30 - Strontium 40 - Copper carbonate 5

So next time you go for a trip in nature do not forget bag and small spade, just in case...

Form - always something to explore

FORM - The shape and structure of an object is an ongoing source of fun, entertainment and challenge for potter as when it comes to clay there are almost no limitations. Pretty much everything what is in your head can be transfer to clay.

I am often asked by bonsai people to make some shapes of my pots in different dimension. Trees are living organisms, unique and original by its nature and so it is up to potter to fit the pot to the tree – not the other way around – it would not make any sense. Over the time I realized that the pure recalculation of different proportion to make pot smaller, bigger or higher just does not work. The form, when transformed by pure calculations does not only FEEL same, usually just plain looks odd. It needs different approach – it needs for me to understand what each form in its original size feels like, what on the form speaks (curves, horizontal shape, vertical shape, edges and details) and then transfer this exact same notion to different size. That seem to work for me much better and although I am still on the start point in exploring forms I like the transformed forms much better and they seem to feel right (I do not like to fire anything, which does not feel right to me and I did almost always destroy those done by pure calculations of dimensions)

I do include some photos to these little thoughts of my, but purely just for fun as pictures never speak much of size. Top bonsai pots are 210x122mm and 216x60mm, the tea boats are 680x110mm and 530x80, the bottom bonsai pots are 250x65mm and 295x107.

I hope you have as much fun exploring forms as I do…

Ash glazes in time of potter’s life

Ash glazes becomes part of wood firer’s life, each seem to define curtain period of potter’s life as over the time one finds that when it comes to ash glazes each batch is original. It can be made from one plant and still there is no guarantee the glaze will be same.

We had this great ash glaze from Japanese knotweed. This plant is listed by the World Conservation Union as one of the worlds 100 worst invasive species and we had it on our property, when we brought it - The only working way to get rid of this all killing and rapidly spreading weed is to cut it, burn all what was cut and keep on spraying all that grow and if necessary again cut it and burn it. After first burn we had quit good amount of ash to work with, the glaze (just wash ash with water) was amazing, our technical porcelain love it. It runs a bit, so Petr accommodate this “skirt” to his teapots to catch drips. It lasted us about 2 years. 

The next batch from freshly grown Japanese knotweed was much smaller and also much different, it run a lot and was more rather greener than golden green. There surely will be time in future, when we again will work with this weed ash, but it did not happened right away, because different ash glaze entered our lives, this time hay ash. Our friend cuted meadow high in mountain for the rare plants to grow again as they did in past, when those meadows were cut every year. As it was high in mountain and no farmer living close wanted the hay, they had to burn it – their car almost couth fire as they did not realized the ash was still warm enough to ignite. So we received very wet (from puting the car fire out) hay ash with parts of burned blanket in it with its own story already. And this glaze was just miraculous – milky yellow glaze with crystals loving almost every clay, we use. It lasted also more than two years. 

Then another hay ash entered our lives, it waited not washed for a while until its time came. It is very much different from the first hay ash we had, more transparent, less crystals forming, but it has this great visual difference when applied in different thickness and this wooden like natural look on one of our stoneware, that we decided not to play with it, but leave it as it is and enjoy its properties.

Different approach we took towards our nuka glaze (usually we mix nuka: 600g of custar feldspar Poběžovice, 400g of silica and 500g of wood ash). This glaze has great look on our stoneware clay Dorda (stoneware clay with addition of iron scaling). Thick, milky fine blue, subtle and not too yowling glaze. When we used new wood ash it changed its properties to more grey, more running, less milky glaze. We add silica (recipes is always just a guide line, no need to worry). So we are back now to our loving, our kind of blue version of this glazes now.

There is walnut shells ash waiting to be washed and tested to see what nature can offer in its unique composition, so perhaps the TIME OF WALNUT ASH is comming soon...