The secret to cool bodies and glazes is alot of testing. But how will you be able to learn from that testing without a good place to store the recipes? Document the successes and failures? Do it in your account at

Alberta Slip Cone 6 Oatmeal

Code: GA6-F
Modification Date: 2015-10-30 18:56:19
Member of Group: AS6

Plainsman Cone 6 Alberta Slip based glaze. It can be found among others at

Alberta Slip Calcined40.037.0%
Alberta Slip40.037.0%
Ferro Frit 313420.018.5%
Titanium Dioxide3.02.8%


Alberta slip is well suited to oatmeal glazes because it already has the iron content needed. Vary the titanium for more or less gloss and oatmeal appearance.

This glaze is very attractive, but one issue you might encounter is pinholing or blistering if it is too thick (a common problem with this type of glaze). Try using it on different bodies and thicknesses to find the best combination. Adjust the frit if you would like it to melt lower or higher. Do not hesitate to reduce the rutile and titanium by a percent to experiment. Getting this glaze working is well worth the effort, not just for the fired results, but for how well it works in the studio. It is actually less troublesome than most others that fire similarly.

This recipe was referred to as GA6-B in past.

How much rutile can a glaze take before it becomes unstable?

How much rutile can a glaze take before it becomes unstable?

The 80:20 base Alberta slip base becomes oatmeal when over saturated with rutile or titanium (left:6% rutile, 3% titanium; right:4% rutile, 2% titanium right). That oatmeal effect is actually the excess titanium crystallizing out of solution in the melt as the kiln cools. Although the visual effects can be interesting, the micro-crystalline surface is often susceptible to cutlery marking and leaching. This is because the crystals are not as stable or durable as the glass of the glaze.

Cone 6 black with a second layer of oatmeal glaze

Cone 6 black with a second layer of oatmeal glaze

The underglaze is G1214M cone 6 black (adds 5% Mason 6666 black stain). Overglaze left: GR6-H Ravenscrag Oatmeal. Overglaze right: GA6-F Alberta Slip oatmeal. Both produce a very pleasant silky matte texture (the right being the best). Both layers are fairly thin. In production it would be best to spray the second layer, keeping it as thin as possible. It is also necessary to adjust the ratio of raw to calcined Alberta or Ravenscrag Slips to establish a balance between drying hardness but not too much drying shrinkage (and resultant cracking).

Calcining Alberta Slip

Calcining Alberta Slip

Calcined Alberta Slip (right) and raw powder (left). These are just 5 inch cast bowls, I fire them to cone 020 and hold it for 30 minutes. Why calcine? Because for glazes having 50% or more Alberta Slip, cracking on drying can occur, especially if it is applied thick (Alberta Slip is a clay, it shrinks). I mix 50:50 raw:calcine for use in recipes. However, Alberta Slip has an LOI of 9%, so I need to use 9% less of the calcine powder (just multiply the amount by 0.91). Suppose, I needed 1000 grams: I would use 500 raw and 500*.91=455.

Out Bound Links

XML to Paste Into Insight

<?xml version="1.0"?>
<recipes version="1.0" encoding="UTF-8">
<recipe name="Alberta Slip Cone 6 Oatmeal" keywords="Plainsman Cone 6 Alberta Slip based glaze. It can be found among others at" id="97" date="2015-10-30" codenum="GA6-F">
<recipeline material="Alberta Slip Calcined" amount="40.000" unitabbr="kg" conversion="1.0000" added="0"/>
<recipeline material="Alberta Slip" amount="40.000" unitabbr="kg" conversion="1.0000" added="0"/>
<recipeline material="Ferro Frit 3134" amount="20.000" unitabbr="kg" conversion="1.0000" added="0"/>
<recipeline material="Rutile" amount="5.000" unitabbr="kg" conversion="1.0000" added="1"/>
<recipeline material="Titanium Dioxide" amount="3.000" unitabbr="kg" conversion="1.0000" added="1"/>
<url url="" descrip="Recipe page at"/>

By Tony Hansen

Feedback, Suggestions

Your email address


Your Name


Copyright 2003, 2008, 2015, All Rights Reserved