Earl Brunner on wed 12 feb 03
I've been using Floating Blue using the following formula:
Floating Blue
Gerstley borate 25
Nepheline syenite 43.8
EPK 5
Silica 18.8
Cobalt carbobonate 1.9
Red iron oxide 1.9
Rutile 3.7
Na2O 0.36 Al2O3 0.48 SiO2 3.25
K2O 0.09 B2O3 0.41 P2O5 0.00
MgO 0.09 TiO2 0.16
CaO 0.40 Fe2O3 0.06
CoO 0.06
I=92ve wanted to convert it to eliminate the Gerstley Borate for some=20
time. I have looked at the following recipe from ClayArt, and noticed=20
that empirically it isn=92t REAL close to the original. My question is,=20
is there a rationale for that? I haven=92t tested mine for leachability=20
or anything yet, but the Emperical is somewhat closer to the original.=20
I was wondering what anyone's opinion might be?
Ron Roy Floating Blue
Frit 3134 36
Nepheline syenite 30
EPK 20
Silica 14
Rutile 4
Red iron oxide 2
Cobalt carbonate 1.4
Na2O 0.41 Al2O3 0.53 SiO2 3.56
K2O 0.06 B2O3 0.44 P2O5 0.00
MgO 0.00 TiO2 0.17
CaO 0.48 Fe2O3 0.06
CoO 0.04
My Test Conversion
Frit 3124 10
Frit 3134 19
Nepheline syenite 23
EPK 9
Silica 7
Cobalt carbonate 1.5
Red iron oxide 1.5
Rutile 3.1
Na2O 0.40 Al2O3 0.48 SiO2 3.25
K2O 0.06 B2O3 0.41 P2O5 0.00
MgO 0.00 TiO2 0.17
CaO 0.47 Fe2O3 0.06
CoO 0.06
Earl Brunner
mailto:bruec@anv.net
Ron Roy on sat 15 feb 03
Hi Earl,
Got behind on my email so I'm late - story of my life these days.
I am going to deny the recipe attributed to me here - it is not close
enough to be one of mine. The main reason I suspect this is because there
is no MgO in it - I have understood for a long time that when you take GB
out and sub in a frit with no MgO you have to supply it - I usually use
Talc.
Yes - yours is closer to the original but suffers from the same problem -
no MgO so I have taken the liberty of revising it - by the way the body of
materials only adds to 68 - am I working with a full deck? Seems to me - if
the main materials only add to 68 then the rutile, iron and cobalt should
be less - oh yes - I see they are.
There is a basic problem using frit 3134 - it has high CaO so you always
wind up with too much CaO for this glaze if you source enough B2O3 - I
think it would be better to use frit 3278 - lets see. Yes - I you can get
it almost perfect using that frit.
You may want to sub in some ball clay for some of the EPK - and maybe a bit
of Red Art to mimic the shale that comes with GB.
I would appreciate it you would do a test on this one and tell every one if
it is viable.
=46rit 3278 - 35.0
Neph Sy - 8.0
Custer - 12.5
Dolomite - 6.0 (I tried talc but too much SiO2)
Whiting - 2.0
EPK - 26.0
Silica 10.5
Total 100.0
Cobalt carb - 2.0
Red Iron 2.0
Rutile - 3.75 up to 4.0 (do a line blend)
Ratio - 6.86 (original is 6.87)
Expansion is 472.32 (org is 479.77) no iron, cobalt or rutile included.
I am trying to form an opinion about durability - looks like it could be -
what do you say John?
Lets call it Brunner/Roy version - if it works.
I am enjoying working with you - got anymore you want bend?
RR
>I've been using Floating Blue using the following formula:
>
>Floating Blue
>
>Gerstley borate 25
>Nepheline syenite 43.8
>EPK 5
>Silica 18.8
>Cobalt carbobonate 1.9
>Red iron oxide 1.9
>Rutile 3.7
>
>Na2O 0.36 Al2O3 0.48 SiO2 3.25
>K2O 0.09 B2O3 0.41 P2O5 0.00
>MgO 0.09 TiO2 0.16
>CaO 0.40 Fe2O3 0.06
>CoO 0.06
>
>I=EDve wanted to convert it to eliminate the Gerstley Borate for some
>time. I have looked at the following recipe from ClayArt, and noticed
>that empirically it isn=EDt REAL close to the original. My question is,
>is there a rationale for that? I haven=EDt tested mine for leachability
>or anything yet, but the Emperical is somewhat closer to the original.
>I was wondering what anyone's opinion might be?
>
>Ron Roy Floating Blue
>
>Frit 3134 36
>Nepheline syenite 30
>EPK 20
>Silica 14
>Rutile 4
>Red iron oxide 2
>Cobalt carbonate 1.4
>
>Na2O 0.41 Al2O3 0.53 SiO2 3.56
>K2O 0.06 B2O3 0.44 P2O5 0.00
>MgO 0.00 TiO2 0.17
>CaO 0.48 Fe2O3 0.06
>CoO 0.04
>
>My Test Conversion
>
>Frit 3124 10
>Frit 3134 19
>Nepheline syenite 23
>EPK 9
>Silica 7
>Cobalt carbonate 1.5
>Red iron oxide 1.5
>Rutile 3.1
>
> Na2O 0.40 Al2O3 0.48 SiO2 3.25
> K2O 0.06 B2O3 0.41 P2O5 0.00
> MgO 0.00 TiO2 0.17
> CaO 0.47 Fe2O3 0.06
>CoO 0.06
>
>
>Earl Brunner
>mailto:bruec@anv.net
>
>___________________________________________________________________________=
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Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
=46ax: 613-475-3513=20
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