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an addition to "new raku"

updated mon 18 mar 02

 

Ababi on sun 17 mar 02


I resend here my letter about lustrous raku

Luster raku



I add here a recipe from Dewit G.'s list
LUSTROUS BLUE
==============
GERSTLEY BORATE..... 40.00 44.44%
SODA FELDSPAR....... 10.00 11.11%
ULTROX.............. 10.00 11.11%
COPPER OXIDE........ 20.00 22.22%
COBALT OXIDE........ 10.00 11.11%
========
90.00

"This glaze yields a metallic blue surface with variations of magenta,
yellow,

and green. After firing, use tongs to place the red-hot pot in a pile of
shredded

newspaper for a about a minute, then a)cover and let cool completely or
b)
remove

from newspaper and quench in water."
++++++++++++++++++++++++++++==

Now My words. This glaze looks very expensive, but you use it very
thin. It looks different on a clear glaze or on the bare ware. This way
, on the bare clay, is my favorite you get it, different every time,
like old copper ware the way they look in the flee markets.
( In Jaffa where there is a flee market they have a special "technique"
how to take a new brass or copper ware and make it old I think with
brown shoes polish).

I changed materials,
Lustrous blue revised by Ababi
================================
LAGUNA BORATE....... 17.00 16.83%
MAGNESIUM CARBONATE. 2.00 1.98% it is important because it makes
the cobalt toward violet
FRIT 3134........... 28.00 27.72%
EPK KAOLIN.......... 3.00 2.97%
ULTROX.............. 10.00 9.90%
COPPER OXIDE........ 20.00 19.80%
cobalt oxide............... 20.00 19.80%
========
100.00

CaO 0.64* 16.41%
MgO 0.12* 2.27%
K2O 0.01* 0.53%
Na2O 0.22* 6.37%
SrO 0.00* 0.01%
TiO2 0.00 0.05%
ZrO2 0.20 11.12%
Al2O3 0.10 4.84%
B2O3 0.66 20.96%
P2O5 0.00 0.01%
SiO2 1.36 37.37%
Fe2O3 0.00 0.07%


Si:Al 13.11
SiB:Al 19.46
Expan 7.63
The result. Above glaze violet not shine enough, perhaps need to be
thicker, or more frit. Below the white 1000C beautiful.
On bare clay violet , again I applied too thin, I had too much water in
the slurry.
I made it on purpose with "your" materials .

This is a very interesting base expensive, but you don't use it in big
amounts.
Yours forever
Ababi Sharon
Kibbutz Shoval- Israel
goes deeply in glazing
ababisha@shoval.org.il
http://members4.clubphoto.com/ababi306910/
http://www.milkywayceramics.com/cgallery/asharon.htm
http://www.israelceramics.org/