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question about mason stains/chemistry

updated sun 15 aug 04

 

ccpottery@BELLSOUTH.NET on wed 11 aug 04


What do Mason Stains add to a slip or clay body other than color?

I think they are mostly neutral since they are a previously
fully fired substance ... but are they still active chemically?

I am going to start experimenting with adding oxides to my
colored clay bodies .... so I was wondering about my starting
point.

Chris Campbell - in North Carolina - starting on another quest!!


Chris Campbell Pottery, llc
9417 Koupela Drive
Raleigh, NC 27615
1-800-652-1008
FAX : 919-676-2062
E Mail : chris@ccpottery.com
Website : www.ccpottery.com
Wholesale : www.wholesalecrafts.com

MarjB on wed 11 aug 04


Afternoon Chris

Some stains and combination of stains will be more refractory. Doubt if it
will be a problem unless you are adding a large percentage to batch. Worth
looking at the formulas and taking that into consideration when testing.
MarjB
----- Original Message -----
From:
To:
Sent: Wednesday, August 11, 2004 11:45 AM
Subject: Question about Mason Stains/Chemistry


> What do Mason Stains add to a slip or clay body other than color?
>
> I think they are mostly neutral since they are a previously
> fully fired substance ... but are they still active chemically?
>
> I am going to start experimenting with adding oxides to my
> colored clay bodies .... so I was wondering about my starting
> point.
>
> Chris Campbell - in North Carolina - starting on another quest!!
>
>
> Chris Campbell Pottery, llc
> 9417 Koupela Drive
> Raleigh, NC 27615
> 1-800-652-1008
> FAX : 919-676-2062
> E Mail : chris@ccpottery.com
> Website : www.ccpottery.com
> Wholesale : www.wholesalecrafts.com
>
>
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melpots@pclink.com.
>

Ivor and Olive Lewis on thu 12 aug 04


Dear Chris Campbell,
As far as I am aware many stains have a Spinel Crystal structure.
Manufacturers would confirm or deny that as a face.
A Spinel structure confers the qualities of an individually high
melting point and low solubility in a silicate melt, which contribute
to their stability. Their sole purpose is to confer colour. Many
require the addition of a fluxing agent when used as underglaze
colours. This is necessary to ensure that they adhere to the clay base
to which they are applied.
Best regards,
Ivor Lewis.
Redhill,
S. Australia.

.

Alisa Liskin Clausen on sat 14 aug 04


>
>I think they are mostly neutral since they are a previously
>fully fired substance ... but are they still active chemically?
>
>


Dear Chris,
Not long ago, I tested many stains for to see if they would fume a tin base.
We were a few on the list that were interested to see if stains would react
with a base. Marjorie had contacted one of the major stain manufacturers
in the US to hear their opinion. It was that because the stains are fired,
that they thought they should not fume.

I chose colors that I presumed had a chrome content to achieve the color
that they are.

In the archives and on my website, you can see the results. All of the
stains fumed.

On the other hand, I use stains widely and in different types of
applications such as painted on bisqueware just diluted with water, added
to base glazes and also as a part basis under glaze, stain, Boron Frit and
Kaolin. I have never experienced any change in the glazes over them except
to color them.

I am still fascinated by my stain fuming test. The word "should" even from
the manufacturer is only as reliable as your personal testing.

Best regards from Alisa in Denmark