Glaze Stains

Your question is a little open ended. There are stains that will not retain the color they were meant to be if fired beyond the temperature range that they are made for. When you buy the stain it will tell you the color and the firing range.

Different oxides (colorants) will do different things in different atmospheres (Reduction vs Oxidation) and in different chemical mixes.

Copper Oxide will be green in an oxidation and if lucky, red in reduction. Chrome Oxide (bright green unfired) with Tin will create pink IF you use a very small amount. Too much and you get a barfy color. Colbalt (Carbonate is pink before being fired, Oxide is black) is almost always blue but can be violet.

Can you clarify your question.

Temp. range is cone9, which in my kiln(Gas) is around 1225DegC. I will be firing in oxidation as reduction will effect the colour. A client want's bathroom basins done in grey and I don't have a grey glaze or the time to make and test one so I thought a grey glaze stain mixed into a base glaze might be the easy way out.

I see that there are stains for glazes, clay bodies, underglazes etc and was wondering what if any difference there is.

I have only ever used oxides and 99% of tha in reduction, no experience with glaze stains at all.

Sam

I can't answer your specific question, but I can tell you to be especially careful in this case. Grey is a well-known problem in that it has to be specifically formulated as grey. It is not, as most people naturally assume, "light black", which will tend to give odd color casts instead of remaining neutral. My feeling is that testing is going to be unavoidable here.

How about a clear glaze over a grey-firing body? Still need to test the specific glaze and body combo, but maybe you already have done that....?

Best regards,

Bob Masta D A Q A R T A Data AcQuisition And Real-Time Analysis

Scope, Spectrum, Spectrogram, Signal Generator Science with your sound card!

the problem really, stems from the fact that glaze isnt paint. its silica and chemistry. you want grey, but if you use iron oxide in reduction you will get brown black, but adding zinc oxide to whiten it will cause it to fire red (and crawl) . there are a thousand or more combinations to even a basic colour, and all of them have thier problems and limitations. soloution? test, test test. keep good glaze log books, fire consistantly and pray to the gods of fire.....

or, but glaze the right formulated colour from one of the wholesalers, like mayco, duncan or spectrum, if you dont like the colours they have, you can always fiddle with the balance. but getting a specific colour is nigh impossible. the same batch of my celedon comes out various shades to green, depending on the humidy and outside temprature. even

10 degrees variance at 2500c can cause the colour to develiop diffrently. not enough air, too much air, the bad phase of the moon...

its what drives us all to drink, and to do that, we need pots to drink out of.....