Oxide Guide

[AdamFG]

Hi All, 

Could anyone recommend an "Idiots guide to Oxides", either a website or a book I can purchase?

I'd like to learn more about how I can use these in their raw state (sorry if that's not the correct term... Am learning as a I go as night school is canceled for the foreseeable  due to COVID-19)

So rather than mixing in  glaze , how can I use the powders I have? I understand I can add the oxide to water to make a wash, but am wondering if I can decorate with powder and bisque fire to set, then clear glaze and fire to final temp of 1240C.  Im making some very textured decorative ware and like the idea of having colour rubbed deep into the texture. 

I know there are lots of variables and no doubt lots of info I've left out, so I was hoping to do some more research myself but am drawing a blank on where to find any good teaching resources. 

Thanks as always, everyone here has always been so kind and generous with their time and advice. 

Cheers

Adam 

[Hulk]

Hi Adam!

There are several threads here on oxide washes - try search string oxide and wash; here's one

Adding A Frit To An Oxide To Create An Oxide Wash - Clay and Glaze Chemistry - Ceramic Arts Daily Community

I don't (haven't yet, any road) use washes, however, I do apply glazes (also underglazes) to texture, wiping to leave glaze in the texture, then dip to cover the area once the work has thoroughly dried. This practice evolved from looking to solve where glaze pulls out and away from texture, where a bit of dust or somewhat prevents the glaze from wetting and therefore sticking in there. I wet my brush, pick up some glaze or underglaze, then brush the area - the water gets sucked into the bisque, and the glaze follows - from there, the wet brush helps to clean the surrounding area and fill the texture, hence not as much sponging away is required. A smallish sponge, turned a bit after each wipe finishes the job.

From latest glaze fire, the mugs, and from a few months ago, small vase - all the chatter marks are filled, eh? This year I've made some progress in throwing successive pieces closer to same shape and size, btw...

 

 

[oldlady]

you can make colored slip with oxides, too.   adding color to slurry left from throwing is the easiest way to make a slip that will work with your clay body.  it IS your clay body so there should be no problem with fit.   if course, if you are using a very dark clay, color may not work for you.

 

[Min]

In ceramics the oxides we predominately use for colourants are some of the transition metals (plus occasionally but not often some of the rare earth metals). Transition metals commonly used are cobalt, copper, iron, chrome, manganese, titanium (works as an opacifier, glaze variegator and colourant) and nickel. Cadmium and vanadium are also a transition metals but they aren't used in oxide form but rather incorporated into stains to make them safer to use. Zirconium is also a transition metal, it's used to opacify a glaze. 

Some of the colouring oxides can be used by mixing with water and brushing or wiping on the wash then wiping it down. Other oxides need something to help them suspend or bind. (as do stains) Temperature you fire to makes a difference also, if you find the oxide wash is powdery after bisque firing that means it needs more flux, either frit or gerstley borate will work. If the wash is too glossy then reduce the flux. 

1 hour ago, AdamFG said:

but am wondering if I can decorate with powder and bisque fire to set, then clear glaze and fire to final temp of 1240C

Yes you can do this, the clear glaze can and probably will have an effect on the final colour, again test first and save the real work until you have it sorted out. 

Years ago June Perry published a long list of oxide washes. She fired to cone 10, as you aren't firing that hot you will need to swap the feldspar for either frit or gerstley borate. Link to it here: http://johnbrittpottery.blogspot.com/2013/03/june-perry-oxide-wash-list.html

 

[blackthorn]

Hi Adam-

The list Min shared above is an outstanding place to start and the price is right.

You mention wanting to use the oxides in powder form.  I'd say "use in their raw state" is not something I see all that often.  That will get very intense right away. Both in terms of the strength of the activity on your ware as well as the messiness you'll encounter in your workspace.  I often use iron oxide, cobalt oxide or carbonate, manganese oxide and rutile straight on the surface of leather hard pieces but will always wear a mask and gloves and throw down a large trash bag for a drop cloth underneath everything.  Sometimes I'll lay a stencil over the work, dust it with the colorant of choice and use a brayer or pony roller to embed it into the surface, and very carefully remove the stencil so as not to dump the excess onto the previously protected spaces.  It takes some time and care for this work.  Or you can just go nuts rubbing on a textured piece and letting it go where ever you touch it. Could be wonderful.  I also intentionally dry colored lumps of clay (with maybe 10% oxide) and grate those over of pieces, dusting them with the colorants, which gives a softer more subtle look.  Too much of any oxide will end of going metallic rather than giving any pure color.   Experimentation will ultimately reveal the path you want to pursue.

Here's one of the freebie pdf files from the Mothership here.  https://ceramicartsnetwork.org/freebies/free-guides/how-to-add-color-to-your-ceramic-art/

 Hope that helps.

 

[neilestrick]

From an educational perspective it's good to learn about oxides, but if your ultimate goal is to simply to do a colored wash on your pots, then for cone 6 and below commercial underglazes are quick and easy and fairly foolproof. They come in a ton of colors, can be blended to some degree, and can be watered down to whatever color intensity you want.

[Chilly]

Plus 1 to everything above, and.......

Take careful notes.  Buy a gram scale and weigh/measure carefully, so when you produce the perfect pot, you can re-create it !