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Cone 6 Oatmeal Glaze Development Project
The G2934 makes a great base glaze, but not without tuning the degree of matteness. The more silky it is the better color and variegator additions look and feel, but a little of the glossy is needed to prevent it being too matte.
Matte:Gloss Blend to create Cone 5/6 glazes
This project is intended to develop silky matte glaze variations using a base made from a mix of G2934 matte and G2926B glossy. Generally, G2934 fires too matte. But mixing in a small percentage of the gloss shines it up enough to get a silky surface. The rate of cooling in the kiln also affects the matteness developed, we are planning to use the C5DHSC or C6DHSC schedules and will tune the blend+variations to work there.
G2934:G2926B Oatmeal - Cone 6
Auto Unity Formula
*This came from a someone who was targeting the "fake Shino" effect in the Mid-Range Glazes book by John Britt. He transplanted the mechanism (the iron, rutile and tin oxide) into our G2934 matte base (with help from the G2926B glossy). While the effect fails as a shino it does produce a nice oatmeal (a standard among middle-temperature potters).
G3933 original photo from customer
The original photo, from the customer, of the glaze shivering on a black-burning body provided the motivation to try it. We were not able to duplicate the shivering, it fits all the bodies we have tried so far.
G3933 on Coffee clay, M340, M340GS
G3933 Oatmeal on M390 at Cone 5 slow cool
XML (to paste into Insight)
<?xml version="1.0"?> <recipes version="1.0" encoding="UTF-8"> <recipe name="G2934:G2926B Oatmeal - Cone 6" id="208086" key="MGt1sa2h" date="2023-09-18" codenum="G3933"> <recipelines> <recipeline material="G2934 Matte Glaze" lookup="G2934" amount="75.000" tolerance=""/> <recipeline material="G2926B Glossy Glaze" lookup="G2926B" amount="25.000" tolerance=""/> <recipeline material="Red Iron Oxide" amount="1.000" added="true"/> <recipeline material="Tin Oxide" amount="5.000" added="true"/> <recipeline material="Rutile" amount="1.200" added="true"/> </recipelines> </recipe> </recipes>
G2934 85:15 Adjustable Matte Black
*Attractive black matte glazes are among the most difficult of all effects to produce. Even slight differences in the degree of matteness are noticeable. Cutlery marking is very visible when the surface is too matte. The key to success is adjustability, both in recipe and firing schedule (more info below).
A stunning contrast between matte and gloss blacks
The clay is Plainsman M370. Fired at cone 6 using the PLC6DS drop-and-hold firing schedule. The inside glossy glaze is G2926BL. The outside glaze base is G2934BL matte. Both recipes contain 6% Mason 6600 black stain. G2934BL is tricky to keep consistent because the matte surface is a product of both the chemistry and the firing schedule. Thus we faced lots of testing when it became necessary to substitute Ferro Frit 3124 for the supposed equivalent, Fusion Frit F-19. Early results showed a little better melting, so the 10-15% glossy we normally add to move the stoney matte toward satin is not needed. However, we still made an 85:15 batch for our more frequent slow-cool C6DHSC firings (otherwise this G2934 mug would have fired too matte). So with the two recipes and two schedules I can produce four surfaces, from gloss satin to stony matte.
Which black base layer produces the best oil-spot effect?
Black matte mixed July 2021
G2934 black vs. G2934:G2926B blend black
G2934Y and G2934 Black - Fast cool
G2934BL brush on version
Four coats. Works very well.
XML (to paste into Insight)
<?xml version="1.0"?> <recipes version="1.0" encoding="UTF-8"> <recipe name="G2934 85:15 Adjustable Matte Black" id="191021" key="LDAoiu25" date="2022-10-24" codenum="G2934BL"> <recipelines> <recipeline material="G2934" amount="85.000" tolerance=""/> <recipeline material="G2926B" amount="15.000" tolerance=""/> <recipeline material="Mason 6600 Black Stain" amount="6.000" tolerance=""/> </recipelines> </recipe> </recipes>