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wood fire/ash glazes/ground up rocks

updated mon 3 may 04

 

Gary Navarre on tue 27 apr 04


Hi Crew,
G. from da U.P. again.In the early 70's I decided to reopen my
vocational rehabilitation case and attended Western Michigan University
to study Geology.Inspired by Cardew's "Pioneer Pottery" and having
hunted oil I figured the knowledge could be usefull.It ended up I
didn't work in oil and got my third academic dismissal,however I did
meet my pal Peter Hayes who lives in Norway in da U.P..We talked many
times about the unique geology of the area, known for its iron
mines(Iron Mountain, Michigan).Many times he would bring out "The Map"
dated 1898(one of the few in existence)of the then known data on the
area.What I am sitting on top of is the upper & and lower Menominee
series of the Algonkian era.This is also called the Menominee Iron
District of Michigan. We're on top of the Hanbury Slate,Randville
Dolomite and Sturgeon Quartzite said to be the highest concentration of
iron in the world. Nearby is the Hermansville Limestone formation. What
I'd been thinking for years was to use these to add to ash and make
glazes, and from some of the posts looks like some of you had the same
idea and did it(I was away for a while,but I'm back).So I'm wondering
about processing the rocks.
The shale is soft enough to powder as is, and the dolomite or limestone
should be a bit more work but easy enough. The quartzite is another
matter. I'd like to know if it can be calcined like granite or is
crushing the only alternative. This rock is a banded hematite/jasper
mix. When all is said and done my plan is to continue with my
experiments the 40/40/20 slip glaze I started in my last kiln.
Persistence takes a long time.
On another note,I've been reading the INTERNET and I've only got 10
pages in the last chapter to finish and I can get to work.See ya.
Gary Navarro
Navarro Pottery
Norway, Michigan

Joseph Herbert on wed 28 apr 04


I have hoped that there would be a movement toward formulation of regional
glazes, or "State Glazes", if you will. Gary's efforts in the UP are a
start. He might gain more local support if he were to use taconite waste
recovered from the lake bottom, but that is another question.

The combination of a clay, some rock dust, and ashes can make rather
beautiful glazes, depend on the constituents and the proportions in which
they are mixed.

In my own case, northern Texas, one could get some mesquite ash from a
barbeque, a local red firing terracotta clay, and rock dust. The possible
choices are the Austin Chalk or some granite dust from the quarrying
operations in the Llano uplift area.

As far as calcining quartzite, that process would likely have little effect
since there should be relatively little fugitive material in the quartzite,
especially the nearly pore-less kind found in the banded hematite deposits
of the UP. One place to look for quartzite powder would be a quarrying
operation that crushes quartzite for aggregate or some other use. The fines
from the operation may be washed into a sump or some other place where
collecting a sample for a glaze trial is possible. Calcining has the
greatest effect on hydrated minerals and carbonates, sulfates, or sulfides.
All these kinds of materials loose gas when heated and change chemical form.
That change often disrupts the particles in a very basic way, producing fine
dust.

The collection of waste materials for rock processing operations, whether
sawing, crushing, sorting, or whatever, can yield possible glaze
constituents. For example, if you were to visit a monument company that
saws granite into grave stones, you could get some of the slurry produced by
the saw blade. That slurry is a fine powder containing all the minerals
present in the granite. Similarly, the dust from lettering operation for
monuments contains all the minerals of the stone, plus some alumina for the
sand blasting grit.

Opportunities abound.

Joseph Herbert

Hank Murrow on wed 28 apr 04


On Apr 28, 2004, at 12:28 PM, Joseph Herbert wrote:

> I have hoped that there would be a movement toward formulation of
> regional
> glazes, or "State Glazes", if you will. Gary's efforts in the UP are a
> start.

Let's not overlook David Stannard's Alaskan porcelainstones, which are
translucent in reduction around C9, and glazed with a mixture of 20%
Fairbanks limestone, 80% Fairbanks porcelainstone. Closest thing to
Jingdezhen on this side of the Pacific. Rings like a bell and deep
bluegreen celadon. over a body you can count your finger through when
held to the light.........Alaskan Gems!

> The combination of a clay, some rock dust, and ashes can make rather
> beautiful glazes, depend on the constituents and the proportions in
> which
> they are mixed.

Amen, Brother!

Cheers, Hank in Eugene

Ivor and Olive Lewis on thu 29 apr 04


Dear Joseph,
Why not use the vices of our materials?
Quartzite is wide open to thermal destruction. Take your cobbles of
the stuff up to or even over cone 04 and cool as fast as you can. Make
use of the Quartz Phase change at 600=BA C to induce a lot of micro
fractures then give it the good old hammer.
Best regards,
Ivor Lewis. Redhill, South Australia

Gary Navarre on thu 29 apr 04


Thanks Ya'll,
Got the mind turning! Yesterday I sat out by the rock ringed fire pit
having cereal with fresh maple syrup and noticed the quartzites had in
fact been fractured by the open heat. Picking a small rock for a pestle
I taped on some pieces and Ivor was correct, heating through quartz
conversion and back will be the ticket to fracture it like granite when
heated. With the quartzite however the mica will not be presest so
levigating that off won't be necessary. Along with the banded hemitite
we have what Pete calls a green stone, sort of frosty semi-translusent
clouds of light green,possably from copper.I'm thinking of a small
catenary arch after the exit flue of the larger main kiln to be used for
this process and later lower temp pieces, although I'll be firing to a
heat work of c/10 or more(I've gone as high c/14 by accident).With the
long slow rise and fall in heat I'll allow a good melt and won't worry
about leaching. If it's all glass its all good.
The granite dust sounds like an alternative but it might be mostly a
mix of many rocks and I'm curious about spacific types.I also have a
couple of different feldspars in the stash downstate. Psycheing up to
spend the time and money for the road trip is next, maybe I'll need to
get a real job for a bit.
As far as starting some movement I wasn't awear there could be one, is
this something else thats socially/politically incorrect like polution
solution bicycle rides, oh god here it comes again I'm havin another
flash back?

Gary Navarre
Navarre Pottery
Norway, Michigan

Ivor and Olive Lewis on fri 30 apr 04


Dear Gary,
Sounds as though your are into some serious geology.
Your "Green Stone". If you have not identified it yet there are
several possibilities. One which springs to mind is Chrysoprase, a
quartz mineral coloured with Nickel, which if of good and uniform
colour, translucency and fine texture can sell for upwards of $200 per
kilo.
Or you might have (saying this with tongue in cheek) some Jadeite
which would take it up to about $2000 per kilo.
Best regards,
Ivor Lewis. Redhill, South Australia

Gary Navarre on sun 2 may 04


Hay Crew,
G.in da U.P.. I was sittin on this log out behind the house here lookin
up the hill I've been lookin for and I thought about that Fung Schwhaway
stuff my last wife was into so I got a rake and cleaned the detritus and
what-not out of the way. I don't know if I'm all lined up with the
vortexes but the fire box will face east.I wish I could get a hold of
Yana the mumbo-jumbo lady downstate who did all the incantations round
the K.I.A.'s anagama. I haven't done that sort of thing for a while and
I'm a little rusty at summoning kiln gods.
The rakeing got the blood flowing so I connected some ideas. "Enclose
the rocks in something in case they pop". And Peter told me the rocks
'round Rickey's camp fire poped from the heat. "Not a good idea to
quench with with cold water or "BOOM". So then I thought "Well, I can
build a Bee-hive or small cat-arch out of red brick to get the rocks hot
and don't have to worry about melting the brick cause I'm not going that
hot".
So ya think we could start a line of localized glazes ah? Thats the
method of my madness in movin here.I've heard Peter tell how we are
standing on the edge of an ancient subduction zone where the first three
continents came together 3.5-4 billion years ago.He even offered the
university use of the farm to do field camps but geologists think this
area was all covered with glacers, wrong!
I was over to Rickie's telling him about Green stone and he showed me
this whitish rock with these green blotches and knows a spot along the
Pine Creek bluffs wheres lots of it, and another spot where titanium
crystals abound. Hell, from what Ivor said I'd make more selling the
rocks than these pots I think are gonna be so neat.But I'm obsessed,I
don't care about the money just the Art. I think this is gonna be really
facinating to see what the glazes will look like. Of course I'll still
make up my stand-by's of Mather Clear,Dunham Blue, and the 40/40/20 ash
slips loaded with individual oxides, the rocks will add a welcome
measure of spontaneity to the mix. Should be interesting.
Gary Navarre
Navarre Pottery
Norway, Michigan

Lee Love on sun 2 may 04


Go for it Gary! Do you heat with wood? Any clay in them there hills?

I just made up a couple more tests (really need to stop mixing and start
glazing.) Have a new shino made of local materials substitution for
Neph Sye. Going to call it Bastarache Mashiko American Shino #1. It
really is durable once it is dipped on and seems to coat greenware
nicely. Will see how the tests go. Anybody oncefire Shinos?

Lee

--
in Mashiko, Japan http://mashiko.org
http://potters.blogspot.com/ Commentary On Pottery

Fred Hagen on sun 2 may 04


Gary, have you used any of the feldspar that is mined in Dickinson County? What experience if any. I'm a yooper also and use the KIA facilities --small world.
Fred

Gary Navarre wrote:
Hay Crew,
G.in da U.P.. I was sittin on this log out behind the house here lookin
up the hill I've been lookin for and I thought about that Fung Schwhaway
stuff my last wife was into so I got a rake and cleaned the detritus and
what-not out of the way. I don't know if I'm all lined up with the
vortexes but the fire box will face east.I wish I could get a hold of
Yana the mumbo-jumbo lady downstate who did all the incantations round
the K.I.A.'s anagama. I haven't done that sort of thing for a while and
I'm a little rusty at summoning kiln gods.
The rakeing got the blood flowing so I connected some ideas. "Enclose
the rocks in something in case they pop". And Peter told me the rocks
'round Rickey's camp fire poped from the heat. "Not a good idea to
quench with with cold water or "BOOM". So then I thought "Well, I can
build a Bee-hive or small cat-arch out of red brick to get the rocks hot
and don't have to worry about melting the brick cause I'm not going that
hot".
So ya think we could start a line of localized glazes ah? Thats the
method of my madness in movin here.I've heard Peter tell how we are
standing on the edge of an ancient subduction zone where the first three
continents came together 3.5-4 billion years ago.He even offered the
university use of the farm to do field camps but geologists think this
area was all covered with glacers, wrong!
I was over to Rickie's telling him about Green stone and he showed me
this whitish rock with these green blotches and knows a spot along the
Pine Creek bluffs wheres lots of it, and another spot where titanium
crystals abound. Hell, from what Ivor said I'd make more selling the
rocks than these pots I think are gonna be so neat.But I'm obsessed,I
don't care about the money just the Art. I think this is gonna be really
facinating to see what the glazes will look like. Of course I'll still
make up my stand-by's of Mather Clear,Dunham Blue, and the 40/40/20 ash
slips loaded with individual oxides, the rocks will add a welcome
measure of spontaneity to the mix. Should be interesting.
Gary Navarre
Navarre Pottery
Norway, Michigan

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