[Clayart] recent work - one glaze three different firings

[vpitelka at dtccom.net]

Hi Carol - 
I am curious as to what inspired these different firing protocols with the
same glaze.  Firing #1 is obviously the most conventional, and the result is
a lovely saturated iron with crystals.  Firing #2 looks a little over-fired,
I would guess from the one hour down-fire soak just 100 degrees below
maturation temperature.  The glaze is still very attractive, but my
observation is based on the mobility of the glaze and the "roll" of glaze at
the bottom, so close to running right off the bowl.  Also, it almost looks
like glaze bubbled a bit on the bottom inside, perhaps from the glaze
pooling there?  And I find it curious that the appearance of the bowl in
firing #3 is not that different from the one in firing #1 despite the
two-hour up-fire hold just 60 degrees below maturation temperature.  Is it
perhaps because the one-hour hold in firing #2 occurred on the down-fire
after the glaze had already become mobile?  

And I am curious why there are virtually no surface crystals in firing #2
despite 2 1/2 hours of down-fire holds between 1750 and 1600.  

This really illuminates how fickle glaze results can be - how even subtle
changes in firing protocol can have a very significant effect on glaze
outcome.  Anyone with some years in ceramics knows that, but it can be
frustrating for those first learning glaze-firing.  My students spent two
years in the advanced clay course series.  They did all their own firings,
and were required to keep accurate firing logs.  Some were careless and
forgot, and others, after firing a few times and getting decent results,
decided they "had it down" and unilaterally decided that kiln logs were
"unnecessary."  Ah, callow youth.  Then, if a glaze came out differently
than in past firings, there was little I could do to help them.   
- Vince  

Vince Pitelka
Potter, Writer, Teacher
Chapel Hill, NC
vpitelka at dtccom.net
www.vincepitelka.com 
https://chathamartistsguild.org/ 

-----Original Message-----
From: carol at knighten.org <carol at knighten.org> 
Sent: Wednesday, December 14, 2022 3:49 AM
To: clayart at lists.clayartworld.com
Subject: recent work - one glaze three different firings

Hi -

Hi -

One glaze, three different firing protocols

http://carol.knighten.org/2022-GlazeTests/2022-12-14-firingEffects/

Carol


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    Carol Marians       
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