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nezumi shino and chinese cobalt

updated fri 11 jun 04

 

Richard Mahaffey on wed 9 jun 04


Hank,
The ones I talked about clearly had an iron slip on them with either
sgrafitto or (not very likely inlaid white/light slip). The color was
not a Ti blue and the glaze had none of the character of a Chun (real
Chinese and the American version developed by Carlton Ball) of which I
am quite familiar. The glaze character was different and did not have
the blue tending to opalescence.
The Nezumi shino pieces I have seen were said to be a few hundred years
old (400 or so) not the new "rediscovered" variety of Arakawa Toyozo.
As you know Arakawa studied shards and whole pieces as well and
developed a way to replicate the older traditional shino. whose
techniques had been lost. It is not clear to me that he was making his
modern shino in the exact same way as was done originally. Arakawa's
were beautiful nonetheless.

Lee and John,
On trying to replicate Gosu Leach has already done it:

Manganese dioxide 40
Black Iron Oxide 30
Black Cobalt Oxide 20
Calcined Ochre 10

This mixture according to Leach approximates the Gosu from pebbles
found in streams in China.

We use this in place of straight cobalt on all of our shiny glazes like
the Limestone clear, celadon and blues, as well as, any chun varieties.
It will produce a black on our matt glazes, so in that case we use
Cobalt Carbonate.

Hope that this helps.

Only two more days until finals are over!

Rick
Tacoma, Washington

Lee Love on thu 10 jun 04


Richard Mahaffey wrote:

> Hank,
> The ones I talked about clearly had an iron slip on them with either
> sgrafitto or (not very likely inlaid white/light slip). The color was
> not a Ti blue and the glaze had none of the character of a Chun (real
> Chinese and the American version developed by Carlton Ball) of which I
> am quite familiar. The glaze character was different and did not have
> the blue tending to opalescence.

I put up the Chun-like shino bowl I've seen at the Mingeikan:

http://public.fotki.com/togeika/jshinos/shino3.html

When I am lucky, I can get crystals like in this glaze from my chun,
which is mostly feldspar.

>
> techniques had been lost. It is not clear to me that he was making his
> modern shino in the exact same way as was done originally. Arakawa's
> were beautiful nonetheless.

You hit it on the nose. Shinos, even in Japan, have not
been handed down in an unbroken like. Arakawa's and Wirt's are both
"rediscoveries." I think Hank mentions potters using a little wood
ash in their shinos. I am guessing this is from the Freer
analysis. Actually, I am guessing that the ash probably came from the
kiln.

> Manganese dioxide 40
> Black Iron Oxide 30
> Black Cobalt Oxide 20
> Calcined Ochre 10

I use Mashiko gosu. costs about $9.00 a bag (it comes wet
and ballmilled.)

John's recipe has much less cobalt, but it turns white shinos blue, as
though the cobalt helps bump the iron into blue. But using this slip
under Wirt type shinos gives you and opaque blue and not a blue like the
photo above. This is John's recipe:

Blue Slip for Shino

EPK 25
OM4 25
G200 20
Flint 20
Borax 5
Zircopax 5

9% R.I.Ox
.25% Cobalt Carb.

This is my Chun blue. I call it Paul's Chun because Paul Morse from
the UofMN gave it to me:

Custer 80
Whiting 7
FLint 7
WoodAsh 4
boneAsh 2
Y. Ocher 1
Bentonite 1

For purple splash: 3% copper slip on raw body. Sky blue on
porcelain or white stoneware. The color of the above Nezumi Shino on
iron bearing Stoneware. I plan on experimenting without ocher and on
different slips and clay bodies.



--
in Mashiko, Japan http://mashiko.org
http://journals.fotki.com/togeika/Mashiko/ Commentary On Pottery