To make this glaze, I started with my natural green glaze as an undercoat. To which I added, in superposition on the undercoat, my white enamel.
White on green
Author : terrajade
Green nature
Here are some pieces made with this enamel:
To find this glaze that I call natural green, my starting point is my Tenmoku recipe. I removed the metaloxide (iron) to experiment with the different oxides in my possession at different concentrations. This type of experimentation allows me to scan a few possible colors on a particular position in a diagram. We often get a lot of waste, but sometimes a notable result appears:
These samples have nickel as the metal oxide. Many times, I had noted tests around browns but I had the good surprise to see a green appear. And what's more, surrounded by a brown as the glaze thickness decreases. This bodes well for some beautiful pieces! So, I decided to explore this track by using the method of research of the cross (Removal or addition of a part of SiO2 or AL2O3).
The result is more homogeneous with a little more alumina or a little less silica. This is why I am continuing my research in this direction by conducting new tests. First with the addition of a little more alumina then by removing silica. Here is the result (we find our cross on the top left):
I choose to select the bottom middle sample which has a beautiful green color that can be seen in nature:
Manganese oxide juice on red sandstone
Here are some examples of my creations with this effect:
In this case, I start with a red clay on which I apply, during the degourdi or on raw piece, a manganese oxide juice. The application of this juice on a piece with reliefs will allow to highlight them.
Manganese oxide juice:
Before going any further, let me explain what a juice is. Nothing complicated, it is simply a liquid (water) and a metal oxide (here manganese). I don't have a concentration to give you. However, the more oxide you put in your water, the more it will be charged. Therefore, when you put down your preparation, you will have less to put. Warning: this may seem like a good idea, but I think it is easier to go through several times with a low concentration.
Explanations:
The juice will settle in greater quantity in the hollows. The water being absorbed by the shard, will therefore leave more oxides in the hollow parts than in the reliefs, which allows to create a contrast between hollow parts and reliefs and to bring out the details on the piece.
Manganese oxide leaves a black color after firing.
The concentration of oxide in the preparation allows to bring more or less marked tints. The fact of passing several layers of this juice also makes it possible to obtain an increase in the deposit of these oxides.
Iron oxide juice on red sandstone
Here are some examples of my creations:
In this case, I start with a red clay on which I apply, during the degourdi or on raw piece, an iron oxide juice. The application of this juice on a piece with reliefs will allow to highlight them.
The juice:
Before going any further, let me explain what a juice is. Nothing complicated, it is simply a liquid (water) and a metal oxide (here iron). I don't have a concentration to give you. However, the more oxide you add to your water, the more it will be charged. Therefore, when you put down your preparation, you will have less to put. Warning: this may seem like a good idea, but I think it is easier to go through several times with a low concentration.
Explanations:
The juice will settle in greater quantity in the hollows. The water being absorbed by the shard, will therefore leave more oxides in the hollow parts than in the reliefs, which allows to create a contrast between hollow parts and reliefs and to bring out the details on the piece.
The iron oxide (whether red or black at the time of installation) leaves, after firing, a brown color tending to purple.
The concentration of oxide in the preparation allows to bring more or less marked tints. The fact of passing several layers of this juice also makes it possible to obtain an increase in the deposit of these oxides.
Lavender blue
Here are a few examples of pieces that I think I've done well with this recipe:
Let's go for the first tests with ashes by superimposing them on my tenmoku. The ashes used are oak, lime, conifer and lavender ashes. On the top line, we will find pure ash superimposed on the tenmoku. On the bottom line, a base of tenmoku with, in superposition, ashes, kaolin and silica.
The sample on the bottom left shows a super interesting effect compared to the other tests. It is an overlay based on lavender ash and a mixture of kaolin and silica. Following this observation, I selected this test and decided to vary in different proportions the kaolin and silica. Here is the result:
The test on the top right shows a beautiful color with nice effects, while retaining a certain opacity. Opacity missing on the first two tests. Following this discovery, numerous tests were carried out to try and "master" this enamel on different pieces. It's not easy, however, as the thickness of the tenmoku and the lavender ash glaze have a direct impact on rendering, as does the shape of the piece.
White flowing on black sandstone
Here are some examples of pieces made with this enamel:
At the beginning of this research, the flowing aspect obtained was not the aspect we were looking for. But, as in many researches, one finds but not necessarily what one was looking for. Initially, I wanted to get a coarse crackle glaze that could resemble the one I had developed for raku. As below:
To try to find this aspect, my starting point was my raku recipe. A recipe for which I did not know the composition of certain components. It was difficult in this case to refer to the fusion diagrams. I decided to vary the proportions of the components of this recipe to try to reach a melting point corresponding to that of the stoneware. A similar effect was obtained but further experimentation will be necessary and will perhaps be the subject of a future article. During these tests, I also obtained a flowing glaze showing brown shades, in addition to the white, more or less marked depending on the thickness of the glaze layer (see the central test below).
The appearance of bubbles leads me to apply the same formulas but with doubled quantities, and here is the result:
My final choice is the central essay!
White
The white flowing glaze on black stoneware that I use to make the white glaze on tenmoku gives a white glaze.
Although this glaze flows on black sandstone or tenmoku, it is not the case on clear sandstone. We notice that small brown dots appear randomly.
Tenmoku
Here are some examples of realizations with this enamel:
Being very interested in ash-based work, I had set myself the goal of finding a recipe for Tenmoku (black glaze with a high concentration of iron oxide) to work on ash-based glazes overlays.
With the help of Daniel de Montmollin 's book "Pratique des émaux 1300°C", I decided to start researching diagram 33. I made my first test tubes, going through the diagram and varying the concentrations of iron oxide. Here's what I get: (the red dot near the sample indicates the one selected for further research)
here in zoom
On the sample, red spots appear. I hypothesize that this is due to the thickness of the enamel, which is thinner in this area. So, to test the hypothesis, I take the formula of this sample and double the quantity of enamel deposited on the test tube.
I then proceeded to a finer test of the iron oxide concentration:
The last test tube (bottom right) corresponds to the concentration used in the previous tests. From this result, I deduce that the concentration used during the first tests is satisfactory to make my Tenmoku.
Oil drop on white
For this effect, I put my white enamel as an undercoat and then, as an overlay, my oil drop enamel.
Some examples of this overlay:
