DHough3777@aol.com on sun 13 oct 96
Dear Fellow Clayheads,
I am having a real problem with pinholing and blistering in my glazes that
have 2 to 4% content of rutile. I have tried just about everything. Christmas
is coming. HELP!!!I fire to cone 11 in heavy reduction. Any and all
suggestions would be helpful.
Dave
Barb & Ray Sapergia on sun 13 oct 96
> I am having a real problem with pinholing and blistering in my glazes that
> have 2 to 4% content of rutile. I have tried just about everything.
Dave,
We had the same problem for about a year and a half, losing about 20% of
each load to blisters - a real nightmare! Our glazes also contained
rutile so we too thought that might be the problem. We tried firing a
slower, hotter bisque, starting reduction later, soaking more, cooling
slower, dampening pots before glazing...no changes at all. We changed
clay companies (after 19 years with the same one), and after a few
firings with the different clay, have had NO BLISTERING - none, not even
a little one! I feel like a potter again, excited about each load, not
terrified about what I might find upon opening the kiln door. I won't
mention the name of the clay company, but you might want to try a change
to eliminate that as a possibility. Good luck - I hope you work it out.
Barb
Elca Branman on tue 15 oct 96
To Barb and Ray Sape...Please do mention the name of the clay and company
you were having doifficulty with;it might save one of us from unhappy
kiln openings..if you's rather do it privately, e mail me at the address
below.
Elca Branman................in the Hudson Valley in
NYstate....elcab1@juno.com
David Hewitt on tue 15 oct 96
In message , DHough3777@aol.com writes
>----------------------------Original message----------------------------
>Dear Fellow Clayheads,
>
>I am having a real problem with pinholing and blistering in my glazes that
>have 2 to 4% content of rutile. I have tried just about everything. Christmas
>is coming. HELP!!!I fire to cone 11 in heavy reduction. Any and all
>suggestions would be helpful.
>
>Dave
>
If its blistering it sounds as if it is over fired. Cone 11 is quite
high.
I wonder if these are a new glaze recipes to you, or ones that you have
used before without any problem. If they are ones that you have used
successfully before, I would wonder about your rutile. Have you just had
a new supply? Rutile, while essentially TiO2, always has a little iron
in it, and if this was more than normal it would give greater fluxing to
your glaze.
David Hewitt
David Hewitt Pottery Caerleon, Tel:- 01633 420647
7 Fairfield Road, Caerleon, Newport, South Wales, UK.
URL http://digitalfire.com/magic/hewitt.htm
"Rafael Molina-Rodriguez (Rafael Molina-Rodriguez)" on wed 16 oct 96
Dave:
There are many possibilities for pinholing. Some post have already
suggested remedies. I would like to address atmosphere and
temperature.
Your post stated that you fired "heavy reduction". What temperature do
you begin reducing, how much is "heavy" ( back pressure with
orange/yellow flame, carbon/soot coming off flame tips, smell of raw
unburned gas) and for how long.
A "heavy reduction" is not necessary, in my experience it can be
counterproductive if you're trying to develop copper reds and purples.
A moderate reduction at cone 06 for approximately 30 minutes is
sufficient. I used to reduce earlier at cone 011-010. You can get away
with this if you're using porcelain or white stonewares but it's not
advisable if you are using a clay body with naturally ocurring iron in it (
ball clays, redart, etc.,...) or a clay body with red iron oxide added.
Carbon coring or black coring will be the result. Cone 06 is a good temp
for body reduction and I believe color in glazes. A light reduction the rest
of the firing cycle to cone eleven will give you the color development you
are seeking.
I have to respectfully disagree with Mr. Hewitt's contention that cone 11
is too hot. Cone 10 is 2381 F and Cone 11 2399 F a difference of only 18
degrees. For a long time I fired to cone 10 tipping but the glazes lacked a
certain sparkle or depth. I now fire to cone 11 almost flat. IMHO, the
added temperature and time involved by moving up to cone 11 makes a
distinct difference in the texture of glaze. Color is another consideration.
As most of you know, atmosphere and temperature play a role in the
development of color in glazes. I used to fire in heavy reduction starting
at cone 010 up to cone 9. I'd open the kiln and be met by load of clear
glazes with tiny specks of red and purple. After I altered my firing cycle
to reducing at cone 06 for 30 minutes and light reduction to cone 11
almost flat the same glazes appeared red and purple. It's my contention
that color develoment begins to occur early in the cycle hence reduction
at 06 for body AND glaze and it's too much reduction for too long and not
the "high" temperature that adversely affects color development. Sure
copper is a very volatile material but I think its volatility is encouraged
/increased by incorrect atmosphere. My theory (DISCLAIMER: I'm no
chemist) is too many carbon molecules taking too many oxygen
molecules from metallic oxides and carbonates used as colorants in
glazes. It's only a theory. I hope this helps.
I would like to give credit to Elmer Taylor, Doug Brown and Paul McCoy
for sharing their firing experiences with me. They continue to be a part
of my development as an artist and educator.
Rafael Molina-Rodriguez
Rmr3431@dcccd.edu
>>> 10/13/96 11:58am >>>
----------------------------Original message----------------------------
Dear Fellow Clayheads,
I am having a real problem with pinholing and blistering in my glazes that
have 2 to 4% content of rutile. I have tried just about everything.
Christmas
is coming. HELP!!!I fire to cone 11 in heavy reduction. Any and all
suggestions would be helpful.
Dave
Talbott on wed 16 oct 96
>----------------------------Original message----------------------------
>In message , DHough3777@aol.com writes
>>----------------------------Original message----------------------------
>>Dear Fellow Clayheads,
>>
>>I am having a real problem with pinholing and blistering in my glazes that
>>have 2 to 4% content of rutile. I have tried just about everything. Christmas
>>is coming. HELP!!!I fire to cone 11 in heavy reduction. Any and all
>>suggestions would be helpful.
>>
>>
..
bisque to cone 05-04
before firing-- cap your top layer of pottery in your kiln with a layer of
kiln shelves...this protects the top layer of pottery from excessive
temperatures
Try firing to cone 9-10 you are probably firing cone 11-12--
...
glaze fire in oxidation to 900 celsius and then reduce at .62 max on the
oxy probe up to cone 9
between cone 9 and 9 1/2 fire in heavy OXIDATION (not to exceed 30 minutes time)
shut the kiln down and close everything up tight to allow for a very slow
cool down as possible and open you kiln up in two to three days
Please let me know if you try this schedule and how it did for you..if this
doesn't work then try changing your glaze formulation..I would do a few
test pieces before doing a kiln load of the "renegade glaze"--good
luck--Marshall
Marshall Talbott
Pottery By Celia
Route 114
P.O. Box 4116
Naples, Maine 04055-4116
(207)693-6100 voice and fax
clupus@ime.net
June Perry on wed 16 oct 96
Dear Dave:
You may have seen these other recommendations but I will list some
suggestions made from other clayart members:
Fire your bisque high - 06 -04
Fire bisque very slowly in an oxidation atmosphere. Reduction at this stage
can cause problems later. Go very slow 1700-1800 F to burn off carbon.
Sieve your glazes through a 200 mesh scrren.
Don't reduce too early or too heavily. (Buy an oxyprobe from Nils Lou).
Fire slowly and give a nice soaking at end but not too long.
Place your pots 1" apart in your glaze firing.
Wet down your pots prior to glazing. You will have to change the thickness of
the glaze to accomodate this.
Manually smooth out any pinholes in the dry, unfired glaze coating.
If all else fails consider a new claybody.
Good luck!
June
Dave & Mary Kuilema on mon 14 jul 97
Hi Richard, if you are still on the list,
I am curious if you ever found the solution to all the problems created by
the new (inferior) rutile that is on the market. I have had similar glaze
problems and used titanium dioxide as a substitute, but its just not as
good as the old rutile.
Finally starting to get back to clay after major back surgery-- and it
feels like coming home.
Mary
Richard Aerni on tue 15 jul 97
Hello Mary,
Yes, I'm still on the list, just have been busy the past few months. I'm
getting packed to head to Ann Arbor today, so haven't got the time for a
lengthy reply, but promise one when I return. There is much to report on
the rutile front (it's not inferior, BTW, just a different product), but
none of it carried forward in a straight-line, satisfactory way. I've
done extensive testing on about 15 kinds of rutiles, with no real
"perfect" answers, and so a couple of months ago decided to work on
taking out any firing variables in the equation by rebuilding my kiln,
reinsulating it, and going the ITC route. I had several awful firings on
the way to the last two, which have been spectacularly good, at least to
my jaded eyes. So, I will go back to testing the rutiles again as I feel
there is some stability on the kiln front. I'm not trying to hide
anything, but it's been a bit of a scramble trying to pull it all
together and still make a living in the meanwhile. So, I'll tell all
when I return.
Thanks for thinking of me,
Richard
Dave & Mary Kuilema wrote:
>
> ----------------------------Original message----------------------------
> Hi Richard, if you are still on the list,
>
> I am curious if you ever found the solution to all the problems created by
> the new (inferior) rutile that is on the market. I have had similar glaze
> problems and used titanium dioxide as a substitute, but its just not as
> good as the old rutile.
>
> Finally starting to get back to clay after major back surgery-- and it
> feels like coming home.
> Mary
Janet H Walker on wed 27 jan 99
...Buy a fifty pound bag, bite the bullet...
Yeah, Louis. Question is, which 50-pound bag? I'm mystified as to how
to get what I want. Who wants the wrong 50-pound bag? The first rutile
i used, back at the dawn of potterhood, was "just right". The stuff I
ordered since then was terrible -- not finely enough milled, although
called "ceramic grade light". It is specky. Totally different effect
in the glazes. I'd be happy if i had 50-lb of the first and very, very
annoyed to have 50-lb of the second. Any suggestions?
Jan Walker
Cambridge MA USA
tgschs10 on wed 28 apr 99
I have three types of rutile on my shelf. One is a dark brown powder, a
second is a light brown and the third is granular. What is the difference?
Can they be substituted for one another in different amounts?
Tom Sawyer
Pamala Browne on thu 29 apr 99
Ceramic grade rutile is light brown.Granular rutile is, um, granular.My
favorite glaze uses the granulated in a chun base with cobalt.It goes
speckled white with a blue background. Another I've tested with granular is
a nutmeg yellow --the rutile speckles brown/blue.I really like the granular
'cuz of the speckling.I have no idea what the dark brown is.The ceramic
grade is more finely ground and therefore disperses thru the glaze, with no
(mostly) speckles.
----- Original Message -----
From: tgschs10
To:
Sent: Wednesday, April 28, 1999 5:40 AM
Subject: Rutile
> ----------------------------Original message----------------------------
> I have three types of rutile on my shelf. One is a dark brown powder, a
> second is a light brown and the third is granular. What is the difference?
> Can they be substituted for one another in different amounts?
>
>
> Tom Sawyer
Eleanor on sun 1 apr 01
I've looked through most of the 1500+ archive entries and a number of
standard potter's books but can't find an answer:
I have a granular form of rutile--separate blue-black shiny grains.
When I sieved glazes (I don't any more--doesn't seem to make a
difference--I mix in a blender), the rutile would not go through even
a 60 mesh screen. I had to scrape it off and put it back into the
glaze mix.
Because I work on a small scale (this is a hobby--but I'm SERIOUS
about it), I make up relatively small quantities of glaze, store them
in 3 qt. OJ containers and apply them by pouring. I shake and shake
and mix and mix the contents of the container before and sometimes
during the pouring process, but no matter what I do, a lot of rutile
winds up at the bottom of the container. Sometimes, when the
container is nearly empty, I'll get a concentration of rutile in the
last of the glaze coating my pot.
I like the effects of the concentrated rutile--streaks, splashes,
spots. I thought of two solutions: use more than the glaze recipe
calls for; put some rutile on a plate and dip a still-damp glazed pot
into it just as I dip a just-boiled bagel into sesame seeds before
baking. I'm not sure the latter solution would work as glaze dries
pretty quickly. I just finished glazing a kiln-load so I'll try these
next time.
I fire at ^6 ox. electric.
Questions: Is there a way to keep rutile in suspension? Is there a
better application method?
Eleanor Kohler
Centerport, NY
with praises for this past week's list monitor--good job!!
don hanson on sun 1 apr 01
Hello: I use rutile a lot. I have a 5 gal bucket of it I have been using =
for years. Seems like I remember there are a couple of types. The one I =
have I think, is one called "ceramic grade". Don't recall the other but =
do remember being told not to use the other one. I have never had the =
problem dicussed on this chat line. Don
C TRIPP on sun 1 apr 01
Hi,
Mia in ABQ mentioned recently that she uses a damp brush to pick up granular
ilmentite and then she brushes it onto the glazed pot. I haven't tried this
yet but it should work for granular rutile.
Regards, Carol
_______________________________________________________
Send a cool gift with your E-Card
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Marjorie Beynon on sun 1 apr 01
Eleanor: I have used "FLOCS" a product I purchased through Tucker's and
this worked to keep a high rutile glaze in suspension. 1/4 teaspoon to 5
gals.
Put rutile or a rutile mix in a seive and sprinkle on the still wet pot as
you finish pouring the glaze. If you can find a baking sieve that has a
handle that you squeese to move the sieves this would be a bit more
controlled. Probably it is advisable to wear a mask while doing this.
MarjB
Donald Goldsobel on sun 1 apr 01
What you have is commonly called granular rutile and what most recipes call
for is ceramic grade rutile of about 150 mesh. The granular rutile I use is
ideal for a fine sprinling in certain areas where I want a certain
response. Too much and it gets very matt and there is no melt into the
glaze. Try the ceramic grade. You can just mix it in and it won't settle.
Donald
----- Original Message -----
From: "Eleanor"
To:
Sent: Sunday, April 01, 2001 9:55 AM
Subject: rutile
> I've looked through most of the 1500+ archive entries and a number of
> standard potter's books but can't find an answer:
> I have a granular form of rutile--separate blue-black shiny grains.
> When I sieved glazes (I don't any more--doesn't seem to make a
> difference--I mix in a blender), the rutile would not go through even
> a 60 mesh screen. I had to scrape it off and put it back into the
> glaze mix.
>
> Because I work on a small scale (this is a hobby--but I'm SERIOUS
> about it), I make up relatively small quantities of glaze, store them
> in 3 qt. OJ containers and apply them by pouring. I shake and shake
> and mix and mix the contents of the container before and sometimes
> during the pouring process, but no matter what I do, a lot of rutile
> winds up at the bottom of the container. Sometimes, when the
> container is nearly empty, I'll get a concentration of rutile in the
> last of the glaze coating my pot.
>
> I like the effects of the concentrated rutile--streaks, splashes,
> spots. I thought of two solutions: use more than the glaze recipe
> calls for; put some rutile on a plate and dip a still-damp glazed pot
> into it just as I dip a just-boiled bagel into sesame seeds before
> baking. I'm not sure the latter solution would work as glaze dries
> pretty quickly. I just finished glazing a kiln-load so I'll try these
> next time.
>
> I fire at ^6 ox. electric.
>
> Questions: Is there a way to keep rutile in suspension? Is there a
> better application method?
>
> Eleanor Kohler
> Centerport, NY
>
> with praises for this past week's list monitor--good job!!
>
>
____________________________________________________________________________
__
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.
Mike Gordon on sun 1 apr 01
Hi,
I don't know if thios would work with rutile but I used to mix granular
manganese with wax resist and brush it on over various clay slips and
one fire reduction at c/5. Nice results. Mike Gordon
Bret Hinsch on sun 1 apr 01
You can try using glazes high in ball clay. These tend to be gooey, and are
more likely to keep things from settling.
Bret in Taipei
_________________________________________________________________
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Steve Mills on tue 3 apr 01
Eleanor,
Up to 3 percent Bentonite is what I generally use to keep *heavy* glazes
in suspension (Harry Horlock-Stringer used to say *Bentonite and every
nite!). Like You I don't sieve; it removes all the interesting bits.
Provided you don't have any Bone Ash in the recipe a dessert spoon per
gallon of a saturated solution of Calcium Chloride is an excellent
suspender for an already mixed glaze (Bone Ash has the reverse effect of
making a glaze to which CC is added set like concrete!).
Steve
Bath
UK
In message , Eleanor writes
>I've looked through most of the 1500+ archive entries and a number of
>standard potter's books but can't find an answer:
>I have a granular form of rutile--separate blue-black shiny grains.
>When I sieved glazes (I don't any more--doesn't seem to make a
>difference--I mix in a blender), the rutile would not go through even
>a 60 mesh screen. I had to scrape it off and put it back into the
>glaze mix.
>
>Because I work on a small scale (this is a hobby--but I'm SERIOUS
>about it), I make up relatively small quantities of glaze, store them
>in 3 qt. OJ containers and apply them by pouring. I shake and shake
>and mix and mix the contents of the container before and sometimes
>during the pouring process, but no matter what I do, a lot of rutile
>winds up at the bottom of the container. Sometimes, when the
>container is nearly empty, I'll get a concentration of rutile in the
>last of the glaze coating my pot.
>
>I like the effects of the concentrated rutile--streaks, splashes,
>spots. I thought of two solutions: use more than the glaze recipe
>calls for; put some rutile on a plate and dip a still-damp glazed pot
>into it just as I dip a just-boiled bagel into sesame seeds before
>baking. I'm not sure the latter solution would work as glaze dries
>pretty quickly. I just finished glazing a kiln-load so I'll try these
>next time.
>
>I fire at ^6 ox. electric.
>
>Questions: Is there a way to keep rutile in suspension? Is there a
>better application method?
>
>Eleanor Kohler
>Centerport, NY
>
>with praises for this past week's list monitor--good job!!
--
Steve Mills
Bath
UK
Ian bogus on mon 18 mar 02
Hello all,
I am just about to start mixing my first batch of glazes (there is a first time for everything). While looking through a catalog I came across a chemical which I did not know which version to get. I am using "Mastering Cone 6 Glazes" (RR and JH). Under rutile the catalog offers "light" "dark" and "granular". I am assuming I do not need the granular rutile, but what are the differences between light and dark rutile? Is there a difference between them, should I purchase one or the other?
Thanks in advance!!
Ian
Richard Aerni on mon 18 mar 02
Ian,
Yes, granular rutile will give a spotted effect, and is hard to keep in =
solution, it being so heavy.
Light, or ceramic rutile, is the same as dark rutile, except it has been =
calcined. For whatever reason, I find that the ceramic rutile =
(calcined) works better in my glazes, but you may not find it so. Why =
not order some of each and run side by side tests?
Good luck,
Richard Aerni
Bloomfield, NY
----- Original Message -----=20
From: Ian bogus=20
To: CLAYART@LSV.CERAMICS.ORG=20
Sent: Monday, March 18, 2002 8:57 AM
Subject: rutile
Hello all,=20
I am just about to start mixing my first batch of glazes (there is a =
first time for everything). While looking through a catalog I came =
across a chemical which I did not know which version to get. I am using =
"Mastering Cone 6 Glazes" (RR and JH). Under rutile the catalog offers =
"light" "dark" and "granular". I am assuming I do not need the granular =
rutile, but what are the differences between light and dark rutile? Is =
there a difference between them, should I purchase one or the other?=20
Thanks in advance!!=20
Ian=20
-------------------------------------------------------------------------=
-----
=
_________________________________________________________________________=
_____ Send postings to clayart@lsv.ceramics.org You may look at the =
archives for the list or change your subscription settings from =
http://www.ceramics.org/clayart/ Moderator of the list is Mel Jacobson =
who may be reached at melpots@pclink.com.=20
artimater on sat 27 apr 02
HEHEHERon said:
neph. sye 2700
frit 3134 1540
flint/silica 455
EPK 305
add:
RIO 100
Cobalt oxide 50
rutile 200
macaloid 110 did not use this
He said rutileHEHE
PAX,
Rush
"I only indulge when I've seen a snake, so I keep a supply of =
indulgences and snakes handy"
http://artimator.com
rush@artimator.com
http://groups.yahoo.com/group/texasceramics/
Artimator Galleries
2420 Briarwood Ln.
Carrollton, TX 75006
972-841-1857
artimater on sat 20 jul 02
Hi Ya'll,
Thank god for "bad" rutile....I collect Frankoma pottery, and I =
have since long before I started making my own....I got the privately =
published, signed by the author, book back in like 1980.....There was no =
other source for info on the pottery back then.....Gloria and I used to =
go a different direction every weekend and scour the antique stores for =
the stuff....If a person did not know the good ones from the bad ones =
they would price them in crazy ways....We would get pieces valued at =
$400 for $4HEHEHE...HOHOHO....That is fun city....We would be busting =
out laughing ALL THE TIME
One of the easiest ways to tell a "good" one from a "bad" one is =
the rutile....Frankoma's source of "good " rutile ran out around =
1960...The new stuff they started using looked kinda like latex house =
paint....yeeech....The old stuff is way cool....There were also changes =
in their clay supply in 1950 and 1970....The old pots made while their =
glaze guru John Frank(Alfred trained by Charles Binns) was alive sang =
songs even though they were mass produced...The new ones suck and I'm =
sure keep old John rolling over and over in his grave...
One of the qualities that adds true value to a piece of pottery is =
time on earth....Frankoma has some shapes they have been making since =
the start of the pottery....The funky latex looking rutile made it real =
easy to tell the old from the new....Often two alike pieces would carry =
a similar price....but one would be wildly more valuable....Nowadays =
there are, I think, four or five books on Frankoma pottery, so even =
those totally devoid of a sense of aesthetics can avoid selling the good =
ones priced like the bad ones....Yep the good ol' days are gone =
forever....
PAX,
Rush
"I only indulge when I've seen a snake, so I keep a supply of =
indulgences and snakes handy"
http://artimator.com
rush@artimator.com
http://groups.yahoo.com/group/texasceramics/
Artimator Galleries
2420 Briarwood Ln.
Carrollton, TX 75006
972-841-1857
Barbara Mueller on fri 27 sep 02
I have a question which came from being at Seattle Pottery a few weeks
ago. What is the difference between Milled Rutile, Ceramic Rutile and
Granular Rutile. Which do I want to use?
Thanks
Barb
Linda Knapp on sat 28 sep 02
I think the right answer would be - "It depends what you want to use it
for." ;-)
If you are using it for glaze Ceramic Rutile is the normal one to
get..... I don't remember the difference in mesh sizes between them but
Granular Rutile will be pretty course - almost like sand. I have thought
of using it or granular Iron Oxide to get spots in glazes. If you go
back to SPS (Seattle Pottery Supply) they have some baggies and vials of
samples hanging over by the glaze raw materials (walk back along the
shelves of bags - they are hanging on the end of one of the shelves to
your across from the brown bags of oxides. ) which will give you an
idea of the size of the different classifications.
Cheers!
Linda
Barbara Mueller wrote:
>I have a question which came from being at Seattle Pottery a few weeks
>ago. What is the difference between Milled Rutile, Ceramic Rutile and
>Granular Rutile. Which do I want to use?
>
>
>
>Thanks
>
>Barb
>
>______________________________________________________________________________
>Send postings to clayart@lsv.ceramics.org
>
>You may look at the archives for the list or change your subscription
>settings from http://www.ceramics.org/clayart/
>
>Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
>
>
>
>
David Hendley on sat 28 sep 02
No one on Clayart knows more about rutile than Richard Aerni.
Since he has singed off Clayart for a while, here is a re-run of
his posting from last year.
David Hendley
Maydelle, Texas
hendley@tyler.net
http://www.farmpots.com
Okay!! Another piece of the puzzle, at least as it pertains to the rutile
question. I've been doing a bit more research, and a lot more fact
checking...when someone like Michael Banks posts and some of his information
is a bit out of whack with what I've been told, I get a little queasy. I've
learned so much from his posts, and from follow-ups of them I've done on my
own, that I feel the need to get things straight when my info differs from
his.
I talked this morning to one of the tech people at the former TAM Ceramics
plant in Niagara Falls, NY. I say former, since it's been bought twice
since my last conversation with them. The new owners are Ferro Corp.
Although they are apparently a division of Consolidated Rutile Limited, of
Australia, which is a division of Iluka Corporation. It's a big hungry
world out there!
Anyway, Ferro (ex TAM) is where I get my rutile from, where Laguna gets
theirs from, and Trinity Ceramics in Dallas, TX as well (according to David
Hendley). They sell a number of different titania and zircon products. The
two I've used and tested are Ruflux 61 (dark rutile) and Ceramic Grade
Rutile. What are the differences between the two? Very little, apparently.
Ruflux (dark) rutile has a mesh size of 325, as does Ceramic Grade rutile.
The Ceramic Grade will pass 99.5% through a 325 mesh screen, while Ruflux
passes 98.5% through a 325 mesh screen. The Ceramic Grade is indeed
calcined in order to eliminate organics that may have been present for one
reason or another. The engineer couldn't remember the exact calcining
temperature, but said it would be a maximum of 1000C, which isn't enough to
affect the crystalline structure. So, Michael, the calcining doesn't affect
anything but the purity. Whether or not other rutile supply companies
calcine their ceramic grade, or light rutiles, I can't say. I intend to do
some more research and find out.
Most of the rutile that Ferro uses comes from Australia. More specifically,
it is mined on the island of North Stradbroke, off the coast of Queensland.
This rutile is in the form of beach sands, which were laid down by wave
action when the mainland igneous rock weathered. It is gathered and
separated into various products, by the processes outlined in the web site,
which I've highlighted below, in case anyone wants to check it out:
http://www.consrutile.com.au/ABOUTCRL/dwnstream.htm
The rutile Ferro sells in the USA is a blend of the Australian rutile sands,
and other rutile sands they obtain from Florida (also beach sands). The
Florida rutile has a lower silica content, but is higher in iron. The
Australian rutile is the major component in the Ruflux and Ceramic Grade
rutile. According to CRL's website, there are about another 25 years worth
of rutile sands on North Stradbroke Island remaining. After the rutile is
separated and graded in Australia, it is shipped to the US, where it comes
to the Ferro plant in Niagara Falls. There it is blended and milled. A
typical analysis of the Ceramic Grade rutile is appended below, although the
engineer stated that every single bargeload they receive has a slightly
different chemical analysis. When they are operating their line, they test
a sample every hour for consistency. He mentioned that they process 3
million tons per year.
They also have mines in Virginia, which are solid rock mines. These they
use specifically for their zircon products, though according to my
information, there are also significant rutile and ilmenite deposits
present.
There are many other sources of rutile and titania throughout the world.
Some of the largest being mined today are located in Quebec, Canada.
Through the use of the sulphate and the chloride process, it is possible to
create synthetic rutile, and purify ilmenite and rutile to much higher
concentrations of titania. Whether any of these products are being sold to
the ceramic industry as rutile, I can't say. At the moment, I'm awaiting
faxes from a number of other sellers of rutile to the ceramic market whose
samples I hold, giving me a chemical analysis and source of their product.
Since these samples range in color from charcoal gray to lemon yellow, it
would be interesting to see where the differences lie.
Lest you think I'm some kind of certifiable wacko on this subject, rest
easy. I've just got an inquiring mind, and a line of work whose integrity
rests upon a relatively stable and constant source of rutile. I've had to
do a lot of this inquiry in order to save my bacon, from time to time. But
I must confess that I find it all pretty fascinating, as well. As I get
more info, I'll be glad to share it with the list, unless I hear a loud
chorus of NOs from the group.
Certified Analysis Report Ferro Electronic Materials
Ceramic Rutile Product #54429 Lot No. 94
SiO2 .69
Al2O3 .20
Fe2O3 .88
TiO2 94.89
ZrO2 .77
V2O5 .55
Cr2O3 .20
P3 .007
S3 .01
Best,
Richard Aerni
Bloomfield, NY
Linda Knapp on sun 29 sep 02
Just a follow up to this -
I was at Seattle Pottery Supply today and asked- the Ceramic Rutile is
the finest mesh size they have next is milled and courser still is
granular.
Linda
>
> Barbara Mueller wrote:
>
>> I have a question which came from being at Seattle Pottery a few weeks
>> ago. What is the difference between Milled Rutile, Ceramic Rutile and
>> Granular Rutile. Which do I want to use?
>>
>>
>>
>> Thanks
>>
>> Barb
>>
>> ______________________________________________________________________________
>>
>> Send postings to clayart@lsv.ceramics.org
>>
>> You may look at the archives for the list or change your subscription
>> settings from http://www.ceramics.org/clayart/
>>
>> Moderator of the list is Mel Jacobson who may be reached at
>> melpots@pclink.com.
>>
>>
>>
>>
>
> ______________________________________________________________________________
>
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
>
>
Barbara Mueller on sun 29 sep 02
Thanks David for pulling that up for me. It was a good read.
Now time for some personal testing. My plan when I'm settled in on the
East Coast is to take all the different grades of Rutile that I can get
a hold of and run similar glazes tests that I did using Rutile (milled
it was what I originally had) vs Titanium. This time I will use Milled,
Ceramic and Granular. Will post when I have completed.
Thanks for the post
B
-----Original Message-----
From: Ceramic Arts Discussion List [mailto:CLAYART@LSV.CERAMICS.ORG] On
Behalf Of David Hendley
Sent: Saturday, September 28, 2002 6:52 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: Rutile
No one on Clayart knows more about rutile than Richard Aerni.
Since he has singed off Clayart for a while, here is a re-run of
his posting from last year.
David Hendley
Maydelle, Texas
hendley@tyler.net
http://www.farmpots.com
Okay!! Another piece of the puzzle, at least as it pertains to the
rutile
question. I've been doing a bit more research, and a lot more fact
checking...when someone like Michael Banks posts and some of his
information
is a bit out of whack with what I've been told, I get a little queasy.
I've
learned so much from his posts, and from follow-ups of them I've done on
my
own, that I feel the need to get things straight when my info differs
from
his.
I talked this morning to one of the tech people at the former TAM
Ceramics
plant in Niagara Falls, NY. I say former, since it's been bought twice
since my last conversation with them. The new owners are Ferro Corp.
Although they are apparently a division of Consolidated Rutile Limited,
of
Australia, which is a division of Iluka Corporation. It's a big hungry
world out there!
Anyway, Ferro (ex TAM) is where I get my rutile from, where Laguna gets
theirs from, and Trinity Ceramics in Dallas, TX as well (according to
David
Hendley). They sell a number of different titania and zircon products.
The
two I've used and tested are Ruflux 61 (dark rutile) and Ceramic Grade
Rutile. What are the differences between the two? Very little,
apparently.
Ruflux (dark) rutile has a mesh size of 325, as does Ceramic Grade
rutile.
The Ceramic Grade will pass 99.5% through a 325 mesh screen, while
Ruflux
passes 98.5% through a 325 mesh screen. The Ceramic Grade is indeed
calcined in order to eliminate organics that may have been present for
one
reason or another. The engineer couldn't remember the exact calcining
temperature, but said it would be a maximum of 1000C, which isn't enough
to
affect the crystalline structure. So, Michael, the calcining doesn't
affect
anything but the purity. Whether or not other rutile supply companies
calcine their ceramic grade, or light rutiles, I can't say. I intend to
do
some more research and find out.
Most of the rutile that Ferro uses comes from Australia. More
specifically,
it is mined on the island of North Stradbroke, off the coast of
Queensland.
This rutile is in the form of beach sands, which were laid down by wave
action when the mainland igneous rock weathered. It is gathered and
separated into various products, by the processes outlined in the web
site,
which I've highlighted below, in case anyone wants to check it out:
http://www.consrutile.com.au/ABOUTCRL/dwnstream.htm
The rutile Ferro sells in the USA is a blend of the Australian rutile
sands,
and other rutile sands they obtain from Florida (also beach sands). The
Florida rutile has a lower silica content, but is higher in iron. The
Australian rutile is the major component in the Ruflux and Ceramic Grade
rutile. According to CRL's website, there are about another 25 years
worth
of rutile sands on North Stradbroke Island remaining. After the rutile
is
separated and graded in Australia, it is shipped to the US, where it
comes
to the Ferro plant in Niagara Falls. There it is blended and milled. A
typical analysis of the Ceramic Grade rutile is appended below, although
the
engineer stated that every single bargeload they receive has a slightly
different chemical analysis. When they are operating their line, they
test
a sample every hour for consistency. He mentioned that they process 3
million tons per year.
They also have mines in Virginia, which are solid rock mines. These
they
use specifically for their zircon products, though according to my
information, there are also significant rutile and ilmenite deposits
present.
There are many other sources of rutile and titania throughout the world.
Some of the largest being mined today are located in Quebec, Canada.
Through the use of the sulphate and the chloride process, it is possible
to
create synthetic rutile, and purify ilmenite and rutile to much higher
concentrations of titania. Whether any of these products are being sold
to
the ceramic industry as rutile, I can't say. At the moment, I'm
awaiting
faxes from a number of other sellers of rutile to the ceramic market
whose
samples I hold, giving me a chemical analysis and source of their
product.
Since these samples range in color from charcoal gray to lemon yellow,
it
would be interesting to see where the differences lie.
Lest you think I'm some kind of certifiable wacko on this subject, rest
easy. I've just got an inquiring mind, and a line of work whose
integrity
rests upon a relatively stable and constant source of rutile. I've had
to
do a lot of this inquiry in order to save my bacon, from time to time.
But
I must confess that I find it all pretty fascinating, as well. As I get
more info, I'll be glad to share it with the list, unless I hear a loud
chorus of NOs from the group.
Certified Analysis Report Ferro Electronic Materials
Ceramic Rutile Product #54429 Lot No. 94
SiO2 .69
Al2O3 .20
Fe2O3 .88
TiO2 94.89
ZrO2 .77
V2O5 .55
Cr2O3 .20
P3 .007
S3 .01
Best,
Richard Aerni
Bloomfield, NY
________________________________________________________________________
______
Send postings to clayart@lsv.ceramics.org
You may look at the archives for the list or change your subscription
settings from http://www.ceramics.org/clayart/
Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.
Kris Bliss on tue 18 feb 03
hi lily yes i'll take that snow....we are cancelling all kinds of winter =
activities ona counta no snow....my family lives out in the bush and =
they are stuck because the river is running water (snow machines don't =
float) we are going to airlift some groceries out to them....weird =
weather..
anyway to the question at hand...
i belive the milled rutile is larger particle size... but i know for =
sure it does not work in my rutile glaze. we got some by mistake and the =
glaze looked like a completly different formula...
kris in sunny anchorage. where we have to restart the ididarod in =
fairbanks because we have no snow.
funkfamily on sat 29 mar 03
Wow, I could get used to having this group around to answer all my =
questions!
If a recipe just lists "rutile" what kind should I use? Light, dark, =
milled, granular? What kinds of results come from each?
Thanks,
Brenda
Marcia Selsor on sun 30 mar 03
As John H. has advised me, rutile comes in many qualities. He suggests
using line blend increments of 1% until you get the desired color. Also
buy enough rutile to last your lifetime because it changes. I have some
that I have had for 30 years. But it doesn't always do what someone
else's recipes says it will do.
Marcia
funkfamily wrote:
> Wow, I could get used to having this group around to answer all my questions!
> If a recipe just lists "rutile" what kind should I use? Light, dark, milled, granular? What kinds of results come from each?
> Thanks,
> Brenda
>
> ______________________________________________________________________________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
>
--
Tuscany in 2003
http://home.attbi.com/~m.selsor/Tuscany2003.html
Bill Merrill on thu 27 sep 07
I'm sure glad that science in the form it is today wasn't necessary to
make good glazes and strong=20
pots in the past. We sure would have missed seeing strong spiritual
pots. Potters from the past knew their materials and developed their
glazes approaching an empirical method using the materials they knew.
It seems to me from what I read is that people have to have everything
perfect before making the art. I know the sharing of ideas is important
and can help others create strong spiritual pots, but what really
matters is that we work hard to produce strong forms. Don't get caught
up in the glaze doesn't add up to 100 syndrome or the glaze isn't any
good.
=20
Bill
=20
billm@pcadmin.ctc.edu =20
Ivor and Olive Lewis on fri 28 sep 07
Dear Bill Merrill,
Peter Anderson was one of the potters who influenced me during the =
twelve months he was teaching at Whyalla. For him, strongly thrown forms =
were paramount regardless of size. He was also a great believer in =
repetition.
Peter had strong feelings about Rutile and Ilmenite. He maintained they =
destroyed good glazes and did nothing to improve bad ones. I tend to =
agree with Peter even today.
That being said, I have found in the intervening years that there are =
occasions where Rutile gives optical qualities that cannot be obtained =
except by firing a Rutile bearing glaze to exceptionally high =
temperatures, in the region of Cone 12.
Sometimes these optical effects ephemeral. At which point Empiricism =
cannot help solve the problem of why we are denied success, a concept =
impressed upon me by Dr. Jim Carney a long long time ago.
Enjoying your contributions to Clayart.
Best regards,
Ivor
mel jacobson on sun 28 sep 08
i purchased a 25 pound bag of rutile in 1966.
it is a nice golden brown. still have about 6 pounds left.
you have to experiment with magic wash.
we use it on everything...sometimes it is ugly as sin.
as i say:
rutile can be maverick...if you depend on it for
all your sales...you will get kicked hard in the butt from
time to time.
tom and betsy wirt sell a ton, but have to remake entire
orders from time to time...that gallery wants floating blue
to be the same every time. hard to do.
(and, tom often does not know what the hell went wrong...he
makes great pots, with a great deal of skill and certainty.
when i goes bad...who knows?)
from minnetonka:
website http://www.visi.com/~melpots/
clayart site:
http://www.visi.com/~melpots/clayart.html
David Hendley on sat 21 jan 12
----- Original Message -----
Titanium in the form of rutile is most refractory. When washes of
rutile are used over glazes pin holing may occur. I use a mix of
Colemanite/Gertsley Borate and rutile for washes over glazes. The mix I
use is a traditional mix of 60 parts Colemanite/Gertsley Borate and 40
parts Rutile. The flux helps to prevent pin holing.
A form of rutile was used on the bottoms of Chinese pots to prevent the
piece from sticking to a shelf. Victor Babu makes a circle of rutile in
the foot area of his platters to prevent the porcelain from sticking,
should the inside of the platters foot warp and touch the kiln shelf.
Bill Merrill
Bill, I have a hard time believing that rutile is the most refractory
form of titanium. My experience tells me that iron is the most fluxing
oxide we use. Rutile is titanium plus iron, so it would seem that
the iron would make it more meltable than pure titanium dioxide?
I don't know, never test it, but this seems logical.
I bet the ancient Chinese potters would have used titanium dioxide
on the bottoms of their pots had it been available to them.
I have continued to use the same overglaze recipes ever since I got
then from John Glick in the '70's. Rutile overglaze is 25% rutile,
25% iron oxide, and 50% celadon glaze. It's just right for producing
those beautiful gold crystalline accents on a glossy glaze.
David Hendley
david@farmpots.com
http://www.farmpots.com
http://www.thewahooligans.com
Bill Merrill on sat 21 jan 12
Titanium in the form of rutile is most refractory. When washes of
rutile are used over glazes pin holing may occur. I use a mix of
Colemanite/Gertsley Borate and rutile for washes over glazes. The mix I
use is a traditional mix of 60 parts Colemanite/Gertsley Borate and 40
parts Rutile. The flux helps to prevent pin holing.
A form of rutile was used on the bottoms of Chinese pots to prevent the
piece from sticking to a shelf. Victor Babu makes a circle of rutile in
the foot area of his platters to prevent the porcelain from sticking,
should the inside of the platters foot warp and touch the kiln shelf.
Bill Merrill
Edouard Bastarache on sun 22 jan 12
Has anyone tried Titanium Dioxide washes instead of Rutile washes?
Gis,
Edouard Bastarache
Spertesperantisto
Sorel-Tracy
Quebec
http://www.flickr.com/photos/30058682@N00/
http://edouardbastarache.blogspot.com/
http://smart2000.pagesperso-orange.fr/bloggs_edouard.htm
http://www.facebook.com/edouard.bastarache
----- Original Message -----
From: "David Hendley"
To:
Sent: Saturday, January 21, 2012 11:17 PM
Subject: Re: rutile
> ----- Original Message -----
> Titanium in the form of rutile is most refractory. When washes of
> rutile are used over glazes pin holing may occur. I use a mix of
> Colemanite/Gertsley Borate and rutile for washes over glazes. The mix I
> use is a traditional mix of 60 parts Colemanite/Gertsley Borate and 40
> parts Rutile. The flux helps to prevent pin holing.
>
> A form of rutile was used on the bottoms of Chinese pots to prevent the
> piece from sticking to a shelf. Victor Babu makes a circle of rutile in
> the foot area of his platters to prevent the porcelain from sticking,
> should the inside of the platters foot warp and touch the kiln shelf.
> Bill Merrill
>
>
> Bill, I have a hard time believing that rutile is the most refractory
> form of titanium. My experience tells me that iron is the most fluxing
> oxide we use. Rutile is titanium plus iron, so it would seem that
> the iron would make it more meltable than pure titanium dioxide?
> I don't know, never test it, but this seems logical.
> I bet the ancient Chinese potters would have used titanium dioxide
> on the bottoms of their pots had it been available to them.
>
> I have continued to use the same overglaze recipes ever since I got
> then from John Glick in the '70's. Rutile overglaze is 25% rutile,
> 25% iron oxide, and 50% celadon glaze. It's just right for producing
> those beautiful gold crystalline accents on a glossy glaze.
>
> David Hendley
> david@farmpots.com
> http://www.farmpots.com
> http://www.thewahooligans.com
>
Cate Ortynsky on sat 21 jul 12
Begin forwarded message:
Thanks for the info on granular rutile versus powdered. I take it that =3D
because the granular rutile offers less surface than the powdered form =3D
it reacts differently ie instead it seems more transparent versus opaque =
=3D
and creates brown spots. doesnt flow as much either. I created a =3D
different glaze but still interesting.=3D20
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