Lili Krakowski on thu 19 may 11
During the most recent Publishing Recipes go-around, I wrote that many =3D
a Top Secret Glaze has escaped into the Free Glaze Zone through. =3D
recalculation.=3D20
I promised/threatened a follow up that should convince One-and-All of =3D
the indispensability of glaze calculation.
Here is my electric fired, c.6, C11 glaze. It is semi-transparent, silky =
=3D
white when opacified. It works well with colorants, especially those =3D
that benefit from high magnesium.
All calculations by GlazeMaster (TM)
C11
Frit 3195 27.50
Dolomite 24.56
Clay 20.43
Silica 27.50=3D20
.077 Na2O
.003 K2O
.352 MgO
.568 CaO
.298 Al2O3
.255 B2O3
2.222 SiO2
As you guessed, it can be made up by volume, using same measure for =3D
each ingredient.
Well, something goes wrong. A drip in the roof reduced a five pound bag =3D
of F 3195 into a mudpuddle. A rodent destroyed the plastic container of =3D
dolomite...Do not worry....these and more disasters have happened in my =3D
glaze pantry.
You dash frantically to your glaze program...or your calculator,, =3D
pencil, and charts. And produce:
Helter Skelter
29.5 Frit--Ferro 3124
17.2 Talc
8.4 Whiting
27.1 Ball Clay--Old Mine #4
8.4 Flint
9.5 Laguna Borate
100.1 Total
.095 Na2O
.016 K2O
.34 MgO
.549 CaO
.276 Al2O3
.238 B2O3
2.091 SiO2
That works, and you go with that for a few years, when miraculously, =3D
you are transported to a British studio, with its "foreign"materials;
And you get
Corgi Bliss
15.7 Frit--CTM Calcium Borate
18.5 Talc
7.8 Whiting
13 Kaolin--Grolleg
21.9 Flint
23 Neph Sy--Podmore
.07 Na2O
.065 K2O
.36 MgO
.505 CaO
.288 Al2O3
.293 B2O3
.002 Fe2O3
2.271 SiO2
See what I mean? I could have clutched C11 to my bosom forever, and it =3D
still could have "gotten out there" in disguise. Or why I do not believe =
=3D
in bosom-clutching glazes. Besides which age does enough damage to =3D
the bosom without help from glaze-clutching!
As I am devoted to high magnesium glazes, I have a stash of high MgO =3D
recipes. And while some are lovelier than others on the clay body I =3D
currently use , the variations are small. The actual changes that come =3D
from new batches of "same label" materials add to the confusion.
Changes in glaze recipes may come about from their modification for =3D
different clay bodies. The "basic" recipe is changed, and transmitted in =
=3D
revised form.
This is why I believe in speaking of glaze "families'. C11 is a high =3D
magnesium calcium borate glaze.=3D20
Lili Krakowski
Be of good courage
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