Recipe of Reliable matt (very) yellow cone 6 glaze

[Danielle Gouvea Costa Resende]

Does anyone have a reliable recipe of a Matt yellow (strong yellow)cone 6 glaze? I'm starting to make my own glazes and my attempts with a barium base turn out to be a beige glaze. Thank you in advance. Greetings from Brazil.

[Norm Stuart]

The answer depends on what type of yellow you're looking for.  If you want a true vibrant yellow, like the bowl below, your choice is a man-made stain from companies like Mason or Cerdec. 

This bowl glaze is colored with 10% Mason Stain 6450 Praseodymium-zinc-silicate.  The color intensity can be turned-down by reducing the percentage of stain.

http://www.axner.com/mason-stains.aspx

This is a link to an excellent semi-matte glaze base developed by Tony Hanson for mixing with color stains.

http://cone6pots.ning.com/photo/stains-in-a-cone-low-expansion-tran...

This photo is taken from this website: http://myclayjournal.blogspot.com/2010/09/firing.html

If you want a more natural "yellow" which is not quite so yellow, you want to use Yellow Iron Oxide, or smaller amounts of red iron oxide, with or without rutile.  You can also use vanadium, which is more orange-gold, or uranium oxide if Brazil is as casual about radioactive materials as France is.

They tend to look more golden yellow when the glaze  is less matte, like the second photo of Gold Brown Transparent.  

These recipes are in our Insight-Live Glaze Database.

Butterscotch

Gold Brown Transparent

[Norm Stuart]

Regarding yellow glaze.  Looking at the components of other yellowish Mason stains, I see there are a couple of other paths to a sort of yellow.

One path I haven't tried is Antimony with Chrome, likely in a ratio of 10 to 1 like red Chrome Tin glazes.  Mason also includes titanium dioxide in their 6485 stain with the Antimony and Chrome.

This is a chunk of natural yellow Garnierite consisting of Magnesium Nickel Silicate, which is more typically green.  The Magnesium makes the appearance matte rather than translucent.

Mason color 6274 uses just Nickel and Silica, similar to this Olive Speckle made with Nickel (carbonate or oxide) and Ferro Frit 5301.

[Danielle Gouvea Costa Resende]

Thank you Norm Stuart for your feedback. I really want a vibrant yellow and I will research on this site you advise me. And I like really matt glazes. I have a blue barium one that is perfect (in blue). But I tried to substitute the oxide for two types of yellow mason stains (12%) and the results are always beige.

I saw on Facebook a matt yellow glaze from a japanese or chinese(?) potter. It was vibrant and really matt. Do you think it's possible in a cone 6 temperature or maybe I should try to find one on low temperature? Is it possible matt glazes on cone 06 or only in cone 6 up?

Thank you again, Best wishes

Danielle

[Norm Stuart]

Mason and Cerdec stains are completely stable to cone 6 and higher.  Mason or Cerdec stains are what you want.  Man-made stains have the advantage of being food-safe as the elements used in the stain are not broken down at kiln temperatures.  These stains are available globally, although this sometimes requires a search.

A matte glaze simply has a microscopically rough surface of crystals which diffracts light.  The typical ways to achieve this are by:

1.)  adding titanium dioxide or sometimes zircopax (zirconium zilicate);

2.)  with semi-matte calcium or zinc base glazes;

3.)  Sometimes with barium or strontium.  Barium and strontium are more typically used to create a color change of copper from green to blue.

The recipe on this test tile is "^6 Lemon Frost" in our Insight-Live Glaze Database.  It uses 10% Mason Stain 6450 Praseodymium Yellow and 5% titanium dioxide.  The titanium dioxide makes the glaze very matte, but also diminishes the yellow color.  To bring out more yellow color, increase the percentage of stain to 20% or so, and/or use less titanium dioxide.

Almost all Mason and Cerdec stains are also stable to Cone 10.  Special "encapsulated" red and orange stains are stable to cone 10, with regular red and orange stable only to cone 8 or so. The encapsulation process mixes the color particles with zircon.

Older pottery had a more limited range of colors because man-made stains were not available.  The largest use of these man-made stains, along with red and yellow iron oxides, are actually as a cement additive to create colored cement and as the colorant in printing inks.

[Danielle Gouvea Costa Resende]

Thank you again Norm. I used a praseodymium stain and a canary stain from Mason with my barium glaze and the results are similar to this photo you added: beige,pale yellow, near white.
With all the information you gave me, I will try ^6 lemonFrost recipe the way you told me or/and another Matt Glaze with no barium.
The kiln I use is not working. It's been refurbished. As soon as possible I'll let you know.
Thank you a lot.
Greetings from Brazil.

[Danielle Gouvea Costa Resende]

Ps:if I take the gloss base you show me at your first answer and try to modify its recipe what ingredients I should change, considering that its recipe is:
Nepheline syenite 35
Silica 21
Epk 10
Whiting 8
Gerstley borate 18?

We don't have anyone who can teach glazes to ceramists or students. We only have English or Spanish books. That's why I feel so lost. Thank you again.

[Norm Stuart]

Matte glazes have a irregular microscopic surface like sandpaper which scatter the light. This is caused by crystaliization.

Titanium Dioxide can create this crystalization.  Rutile is an impure form of titanium dioxide.

High levels of calcium, zinc, strontium of barium also form mirco-crystalline matte surfaces.  The first two are often called Calcium Semi-mattes and Zinc Semi-mattes. Ingredients like Calcium Carbonate or Wollastonite are added.

Increasing the alumina to silica ratio can also make glazes matte, but this sometimes comes at the expense of the glaze not fully melting.  Unmelted glazes are not food safe, but are almost always matte.  Use less silica and more kaolin or clay, or add alumina hydrate.

Danielle Gouvea Costa Resende said:

Ps:if I take the gloss base you show me at your first answer and try to modify its recipe what ingredients I should change, considering that its recipe is:
Nepheline syenite 35
Silica 21
Epk 10
Whiting 8
Gerstley borate 18?

We don't have anyone who can teach glazes to ceramists or students. We only have English or Spanish books. That's why I feel so lost. Thank you again.

[Danielle Gouvea Costa Resende]

Thank you for being so generous. I will study everything carefully!

[Harold Roberts]

This is a yellow matte glaze that I use. There is another overlap glaze I placed on the rim. You can see it more clearly on the cups.

Speckled Yellow Matte

Gerstley Borate ….......02
Barium Carbonate .......15
EPK ….......................23
Spodumene …............27
Wollastonite …...........33

Iron Oxide .....02
Tin Oxide ......04

the overlay is this glaze,

Terra Cotta Matte

EPK ----------------------- 14.0
Bone Ash ---------------- 9.5
Talc ------------------------ 9.5
Dolomite ---------------- 19.0
Nephelene Syenite -- 48.0
Iron oxide --------- 1.0
Tin oxide ---------- 5.0

[George Lewter]

This is a yellow I've been meaning to try, and will soon. Image and text from Creative Creek Artisans

Ron's Fall Yellow

Nepheline Syenite - 35.5
Ferro Frit #3134 – 13
EPK - 19.5
Dolomite - 16
Whiting - 8.5
Bone ash - 7.5
Bentonite - 2
Tin Oxide - 4
Red Iron Oxide - 1.2 
This is named after Ron Roy who provided me with a great deal of help in developing this mat yellow glaze. This glaze must be thin to medium thickness. Too thick and it will blister. Dick White reports nearly the same surface and color in oxidation.

You may want to check out the oxidation specific glazes on their site - http://www.creativecreekartisans.com/creativecreek_cone6ox.htm

[Norm Stuart]

Barium glazes are beautifully matte, but I'd be hesitant to use them on functional ware without doing a leech test.

It is a beautiful yellow.  Hopefully the barium ends up bound to something in the glaze which makes it insoluble.

Tin and iron without the barium create nice colors without the matte, like Bailey Shino.

[Harold Roberts]

Yes, matte glazes tend to be soft but this one is very high in silica and very durable. I have been using it since 2004 and some of my bowls and mugs have been through countless dishwasher cycles and they look like they were fired yesterday. I have substituted zinc oxide for the barium one for one and it works almost the same.