[AtomicAxe]

Red mason stains are largely sensitive to the glaze, but not unstable. The thing that effects a red mason stain (and many mason stains) is Tin in the glaze. Some Ferro frits and other low fire fluxes contain tin to some degree so planning your ^6 glaze is essential before investing in sometimes rather expensive mason stains.

If you have any questions about if your glaze has anything with Tin in it ... let me know ... I'll crack open the books and look it up.
Or check Digitalfire ... it's rather good about that.

[docweathers]

I will watch out for tin in my Mason stain glazes. I've also heard that zinc may be a problem. Is that true?

I will have to research my ferrofrit's to see which ones of them have tin. I never thought about that possibility.

In terms of cost of Mason stains, Axner seems to be the cheapest.


Larry

[AtomicAxe]

Yes, zinc is another big one, some colorants generally pinks, bright neonish colors and some reds react badly with zinc ... turns them grey. check for that as well.

[Marcia Selsor]

Dear Doc and Atomic,
Here is a list of pinks and reds from mason. Most of these stains include tin. Their reference codes are mostly 3,5,9
So do not use with zinc.
Marcia

http://www.sheffield...es/pink_ref.gif


Reference Code:
1 = Can be used as body stain in porcelain at high temperatures.
1a = Use as body stain only.
2 = Maximum temperature - 2156°F (1180°C)
3 = Maximum temperature - 2300°F (1260°C)
4 = Maximum temperature - 1976°F (1080°C)
5 = Do not use zinc in glaze
6 = May be used with or without zinc
7 = Zinc not necessary but gives better results
8 = Best results with no zinc
9 = Glaze must contain 6.7 - 8.4% calcium oxide (12-15% CaCO3)
Above information from Mason Stains. Testing
Recommended.

[AtomicAxe]

Thanks Marcia. Good resource.

Personally i've never been one to use mason stains ... too bland since it just makes this solid color with no characteristics. Nice for a liner and the few mason stain glazes I used in the past were for liners on mugs (lime green liner with an oil spot on the outside for example) but general rule, make a base that you can use any mason stain with so just avoid all zinc and tin in the glaze and you will be fine.

[TJR]

AtomicAxe, on 11 March 2013 - 08:08 AM, said:

Thanks Marcia. Good resource.

Personally i've never been one to use mason stains ... too bland since it just makes this solid color with no characteristics. Nice for a liner and the few mason stain glazes I used in the past were for liners on mugs (lime green liner with an oil spot on the outside for example) but general rule, make a base that you can use any mason stain with so just avoid all zinc and tin in the glaze and you will be fine.

Atom;
The reason that I avoid Mason stains is that they are not fine enough for on-glaze brushing. [see gallery]. I use iron ox., cobalt carb andChrome ox. I use a Degrusia inclusion stain for on glaze reds at cone 10. My purple glaze has tin and copper in it. The reds are not affected. I will get you the number of the stain. Not in the studio right now. It's very expensive, but goes far.
TJR.

[AtomicAxe]

you can ball mill the glaze with a mason stain and make them fine and equally held in suspension ... but really .... eff that.

[JBaymore]

AtomicAxe, on 11 March 2013 - 08:47 PM, said:

you can ball mill the glaze with a mason stain and make them fine and equally held in suspension ... but really .... eff that.

Remember not to ball mill (or mortar and pestle) anything (slips, underglazes, overglazes, stains) that contain inclusion (encapsulated) cadmium bearing stains......... changes the Cd release.

best,

...................john

[Marcia Selsor]

I find Mason stains to be ground finer than metallic oxides like copper and cobalt.
I remember 20 or 30 years ago that wasn't the case. But it seems they are very fine.
When I add 0.02% to a glaze to change the tinge of it and have no spotting, I am happy.

Marcia.

[docweathers]

bciskepottery, on 23 February 2013 - 04:49 AM, said:

Try http://www.uspigment.com/

Axner is significantly cheaper

[Marcia Selsor]

U.S. Pigments list is for the pound price.
Axner's Mason Stains , not the closeout list, are 4 oz or a 1/4 pound. Usually Mason Stains are list by 4 oz. or 1 pound. Some suppliers list both quantities.

Marcia