The test on the right appeals to me with its satin finish and shades of black, green and white...
I try again, weighing the ingredients to obtain a finer result than before. In fact, for the previous test, as is the case when I start from an existing base, I don't weigh all the ingredients, I take a volume of glaze that's already ready and add the metallic oxides to quickly see if a lead can be taken further. This is the case here, so I give it another try:
It seems to be interesting to dig between the second and third attempts. I carry out a new test with a concentration between the second and third test. I also use less material as the enamel looks runny:
Once again, the lower concentration of cobalt seems too dark. Unable to weigh a lower concentration of cobalt with my equipment for testing on a wafer, I prepare a larger volume of enamel to halve the concentration and test it on a larger piece:
It's very close to what I'd like. On the other hand, the rendering isn't blue enough.
New test with a cobalt concentration 50% higher than before:
The result is satisfactory! I then carry out my famous thickness test:
The test on the right suits me with its variations of green and orange.
I try again, weighing the ingredients to obtain a finer result than before. Indeed, for the previous test, as when testing from an existing base, the ingredients are not weighed. Instead, I take a volume of ready-made enamel and add the metal oxides to quickly see if a lead can be further developed. This is the case here, so try again:
I try again, weighing the ingredients to obtain a finer result than before. Indeed, for the previous test, as when testing from an existing base, the ingredients are not weighed. Instead, I take a volume of ready-made enamel and add the metal oxides to quickly see if a lead can be further developed. This is the case here, so a new trial centered on the middle sample:
In the second row, we observe a fairly white glaze with significant braiding. The addition of India ink on the third sample clearly reveals this braiding, reminiscent of a Raku firing.
So I decided to direct my tests in this direction:
The air bubbles seem to have disappeared. I select the sample on the right and glaze a new piece:
The result is much more convincing, but I would have preferred a whiter, less transparent glaze. I then carry out another test (control sample above), adding: bone ash (row 1), Zinc Oxide (row 2), Zirconium Oxide (row 3) and Colemanite (row 4):
Tests with Zinc Oxide, Zirconium Oxide and Colemanite cause the braiding to disappear. However, the braiding persists with bone ash. New test on a part with a concentration between the first and second test of row 1:
The result is a little disappointing, certainly due to the enamel thickness again being too thin. I therefore carry out a thickness test:
The hypothesis seems to be confirmed: a greater enamel thickness (tests on the right) creates the desired effect. I therefore carry out a new test by increasing the thickness:
To obtain this "Dandelion flowers" glaze, I started with my " Lychee" glaze. In fact, this very clear enamel has a good quantity of Titanium, so I wanted to observe the range of colors I could develop from this base.
I therefore carried out tests by weighing the same quantity of " Litchi " glaze (already prepared) and adding different oxides in different proportions. This imprecise method has the advantage of enabling me to carry out a large number of tests quickly, without having to do a lot of weighing. Following these tests, the most interesting ones, if any, can be confirmed by going back to the weighing method.
Here is the result of this first test, with the addition of Copper Oxide in various proportions:
I really like the third sample. So I decide to try again by actually weighing each raw material to determine the right amount of Copper Oxide for each:
The fourth sample is my favorite! However, the glaze seems very runny. I then make a progression of Silica:
The first sample selected, I then decided to make an Alumina progression using Kaolin :
I keep the medium sample and proceed with my thickness test: