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vol/ash/glaze

updated sat 9 jan 99

 

mel jacobson on fri 8 jan 99

i have used volcanic ash mixed with gertsley borate as
my school base for 30 years.
it, at best, has three qualities that every teacher will love.
easy to mix............60 ash, 40 vol, some zircopax.
so that is 60 lbs.ash 40 lbs vol and 2lbs zirc.
it stays in suspension.
it hardens like rock on the pot. (does not flake off.
cheap to make.
fires from cone 1 to 7
cone 1 is semimatt, cone 7 almost runs.
it is not a finite glaze........changes, varigates,
takes any colorant...........if you are real fussy, don't use
it..............it is like shino..........never really know.
but that is good for kids and newbies...........do not
get too deep into prediction........take what the kiln gives you.
anyway.
several commercial potters use it, and love it.
for the above reasons.
but, for any studio with multiple users, schools, community
ed...........it is a star.
did a piece for claytimes about three years ago.......
all the details.
mel/mn
p.s. you can slide this glaze..........for example the lori leary
raku is 70 gert, 30 ash.........works.
it is also a cone 10 glaze...........90 ash, 10 gertsley.
or just all ash to cone 11.
it is fun to mess with, slide the scale.
you might learn something........then tell us all.
http://www.pclink.com/melpots