Using raw oxides to color glass

[chelseasouthard]

Hello All!
Recently, I moved somewhere where it is very hard and expensive to get frits delivered but it is very easy to get raw oxides and chemicals like, pure cobalt, copper oxide, rutilo, chrome oxide, potassium permanganate etc and I have a stock pile of bottle and window glass.

At the same time, I was given a bunch of these chemicals from a local retired glass artist who now does not remember exact how she used them to add to her bottle and window glass to color them. She mentioned something about vaguely remembering the use of frit 3419 as the base then adding the oxides to that to produce many different types of colors. However it seems you cannot get Ferro Frit 3419 anymore so I am looking for a new solution.

I have attached an image of the documentation she has regarding how much of each oxide she used with 30grams of frita (frit en español) along with the sample plate with the results. So this does work, she did do it but I cannot seem to find any information online about the details of how its done at full fuse temperatures. I know about making furnace color batches in a hot shop, adding oxides to the color mix from a source like Spruce Pine https://www.sprucepinebatch.com/glass-batch/ and heating up to 2250-2400°F during charging, but that is not what I'm trying to do here.

If you have any ideas:
1. Suggestions for a new type of base frit that I can order in a large bulk quantity that will be capable of accepting these oxides and making colored glass with float and window glass.
2. A way to make a base frit or something to add to the oxides that is capable of doing the above.
3. Any other ideas about how to accomplish this.

Please don't just tell me to go order bullseye frit and be done, I understand there are many variables and it will be difficult.
But I want to figure out how to make this work.
I love experimentation and it is a important part of my process to explore these kinds of challenges.

Thank you!
Chelsea

[Brad Walker]

See here for a little more info: viewtopic.php?p=364187 There's a nice chart about half way down the thread

Most of the Ferro frits are no longer being made, but you might try some of these: https://ceramicsupplyusa.com/product-category/frits/ Or perhaps a local pottery supplier. As you no doubt know, these frits are most often used in pottery glazes, so a good potter might be able to suggest a substitute.

The folks at Pete VanderLaan's board may also have some suggestions. They know a lot more about glass chemistry than I do: https://talk.craftweb.com/forumdisplay.php?s=&forumid=4

[Terry Gallentine]

I use cobalt carbonate mixed with a very fine frit and it works well. I have been doing this for quite a while and most of the lead bearing frits I used to use are no longer available. I used to use 905 flux from Fusion but they have replaced it with something that doesn't have lead (I am not sure what their present suggested substitute is). Their fluxes seem to me to be finely ground frits (similar to the particle size of Mason Stains) that can be used to alter the firing temperature of glass or glazes. I also mixed their fluxes with Mason Stains to make something similar to glass paints that I screen printed with. There are other oxides and carbonates that work but I used cobalt carbonate because it is such a potent a colorant.

[chelseasouthard]

Wow this is great!
Thanks for all the links and information, I will check them all out and call the suppliers tomorrow to see what would be best for my applications.
Would be great to find an alternative to the lead based frit if it can accomplish a similar outcome.
I was wondering about mason stains actually, very cool that I could potentially use those when they become more accessible to me.
Finding a glass paint recipe that I can make myself would be super since buying that is non-existent where I am.

Really appreciate all the feedback.
Ill let you know what I find out!
What a great experience for my first post on this community forum.