lili krakowski on sun 23 nov 03
Sam asked about yellow ochre the other day and there were answers, but =
little more.
Ochre is a wonderful material, and interesting to use.
It seems to me far more plastic than iron oxides, maybe because it is =
less refined. It is great in slips.
I use Cooper's Black Slip which contains it.
Red Clay 60
Yellow Ochre 30
Red Iron Oxide 10
Leach writes:
"Ochres, siennas and umbers are all natural earths containing from about =
5 per cent. to 12 per cent. of iron. Some are highly platic and may be =
used for colouring bodies or as slips. Calcined they are often useful =
in stoneware glazes, especially celadons."
And Leach tells that the St Ives Red Slip is "Pure local raw ochre."
He has 3 ochre using glazes.
"Leach's Korean Type:
Feldspar 25
Limestone 25
China clay 6.5
Pike's clay 20
Quartz 20
Calcined ochre 2
Red Iron Oxide 1.5
This is c.7-9 (I assume Seger?) Amber in oxidation and Quiet =
Grey-green in reduction
Hamada's Lung Ch'uan Celadon
Feldspar 64
Pine Ash 27
Calcined Ochre 9
Amber in Oxidation, Heavy dull green in reduction. Bottle green when =
hard fired. c.6-8
Don' t know what "hard-fired" means. Sorry
Kenzan Celadon
Feldspar 62
Medium Ash 18
China Clay 12
Quartz 2
Calcined Ochre 6
Red Iron Ox. .12
NB> the Fe203 is decimal point 12
And amber in oxidation, transparent olive green in reduction, c.7-9
I am intrigued by the notes: "The ochre, iron, quartz and any coarse =
ash should be ground in a pot-mill, the alter native is an opaque =
mottled effect beautiful in itself."
And no idea what a pot-mill is either. From the context, elsewhere in =
the book, I take it to be a ball mill.
This is getting too long. So tomorrow we do Part II
=20
Donald G. Goldsobel on fri 28 nov 03
Is yellow iron oxide the same as yellow ochre? I ask because I purchased
some yellow iron oxide and it was light and fluffy, not dense and heavy like
red iron.
Donald
----- Original Message -----
From: "lili krakowski"
To:
Sent: Sunday, November 23, 2003 5:30 PM
Subject: yellow ochre and a a bit of titanium PART I
Sam asked about yellow ochre the other day and there were answers, but
little more.
Ochre is a wonderful material, and interesting to use.
It seems to me far more plastic than iron oxides, maybe because it is less
refined. It is great in slips.
I use Cooper's Black Slip which contains it.
Red Clay 60
Yellow Ochre 30
Red Iron Oxide 10
Leach writes:
"Ochres, siennas and umbers are all natural earths containing from about 5
per cent. to 12 per cent. of iron. Some are highly platic and may be used
for colouring bodies or as slips. Calcined they are often useful in
stoneware glazes, especially celadons."
And Leach tells that the St Ives Red Slip is "Pure local raw ochre."
He has 3 ochre using glazes.
"Leach's Korean Type:
Feldspar 25
Limestone 25
China clay 6.5
Pike's clay 20
Quartz 20
Calcined ochre 2
Red Iron Oxide 1.5
This is c.7-9 (I assume Seger?) Amber in oxidation and Quiet Grey-green
in reduction
Hamada's Lung Ch'uan Celadon
Feldspar 64
Pine Ash 27
Calcined Ochre 9
Amber in Oxidation, Heavy dull green in reduction. Bottle green when hard
fired. c.6-8
Don' t know what "hard-fired" means. Sorry
Kenzan Celadon
Feldspar 62
Medium Ash 18
China Clay 12
Quartz 2
Calcined Ochre 6
Red Iron Ox. .12
NB> the Fe203 is decimal point 12
And amber in oxidation, transparent olive green in reduction, c.7-9
I am intrigued by the notes: "The ochre, iron, quartz and any coarse ash
should be ground in a pot-mill, the alter native is an opaque mottled effect
beautiful in itself."
And no idea what a pot-mill is either. From the context, elsewhere in the
book, I take it to be a ball mill.
This is getting too long. So tomorrow we do Part II
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Lee Love on sat 29 nov 03
----- Original Message -----
From: "Donald G. Goldsobel"
> Is yellow iron oxide the same as yellow ochre?
Yellow ochre is a natural iron bearing clay.
--
Lee in Mashiko
"Few are those who see with their own eyes and feel with their own
earts." -- Albert Einstein
http://Mashiko.org
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