Monday, October 19, 2015

What is in your store bought glaze or additive?

I was talking with someone and they wanted to know what Flocs was made of?! They said the manufacturer wouldn't say...but the do have to disclose an MSDS or SDS on their website. They often try to do the minimum but let's looks at FLOCS.

First just Google "flocs MSDS" and you get:

Which shows that Flocs from Great Lakes clay is calcium chloride, potassium chloride and sodium chloride. It is 73% water, 25% calcium chloride and small amounts of potassium chloride and sodium chloride.

Then Google "Calcium Chloride" and you can read about salts and flocculation and other uses;:

Then there is Floc:

which shows that aluminium chlorohydrate is the main ingredient 30-60% mixed with water >60%.

then google the ingredient and you get :

It is a flocculant : "Aluminium chlorohydrate is also used as a flocculant in water and waste water treatment processes to remove dissolved organic matter and colloidal particles present in suspension."

So you see in less than 5 minutes you can figure out what is in it. We have learned something! Vinegar (acid) is a flocculant, as is muratic acid ...and Epsom salts is a salt that acts like an acid as is calcium chloride and now aluminium chlorohydrate !

Image result for gold glaze john britt
Now, say you have a glaze you like and want to duplicate it. But you need to clue on the colorants...just google the name and msds. So let's take :

Spectrum 1112 Metallic Gold Glaze 

First google it. There are many suppliers so I just picked one:

Then you google the name and MSDS. Sometimes you have to vary the words in google to get a good in this case I used:

Spectrum msds 1112 Metallic Gold Glaze msds msds

and got:

so in this glaze is :

45.0-65.0% Silica
0.5-2.0 %   Potassium
0.5-2.0 %   Calcium
0.5-2.0 %   Sodium
4.0 - 8.0 % Aluminium
0.5-3.0 %   Boron
0.5-2.0 %   Strontium

0.5-2.0 %  Red Iron oxide 
3.0- 6.0%    Copper oxide
25.0 - 35.0% Manganese oxide

So you know that this is a manganese saturated glaze with copper and iron.

I have a bunch of them in my book (The Complete Guide to Mid-Range Glazes page 140) Or you can google "manganese saturated glaze recipes cone 6 electric" and a bunch of sites come up with recipes.

In my book I have them listed side by side so you can see and compare. But Gold Metallic is the standard. 

It doesn't work on all glazes ..e.g. Coyote : You get :

BUT read that and the FOOD SAFE part...very interesting!! But they don't specify what is in each glaze. 

Now let's try Laguna Morrocan Sand Glazes:

And my first love CHUN RED MS - 32 you get :

So you know it is a Silicon Carbide electric red because the SiC - 1% but they don't list know they need copper oxide. They do list Zinc, Lithium, Barium and Tin oxides. 

So on page 103 of my Mid Range book you see recipes for Artificial Reds SiC...and you see similar recipes that will get you started .  Like Copper Red on the cup above. Pretty close to Chun Red.


  1. Very cool, this would be a great way to create variations using the premixed glaze.

  2. John,

    Excellent work on deconstructing glazes.



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