search  current discussion  categories  materials - misc 

the pure and impure (sources of oxides) ????

updated thu 4 sep 03

 

Lily Krakowski on sun 31 aug 03


Rutile is impure titanium. Ilmenite is even more impure titanium. Iron
Chromate is a combination-- I gather natural--of (you guessed it!) iron and
chrome.

I further gather in my hunt for a particular slip/glaze combo that rutile
and ilmenite, and, I would guess, iron chromate-- will vary over the years.
(My rutile dates back to Eagle Ceramics! but it will run out)

Is there any advantage in using the natural combos? Or would I be ok with
using iron and titanium, and iron and chrome? Does the natural combination
of materials have a specific benefit in the melt?

Gurus and guresses--I thank you in advance. And yes, I checked my
books--duh.





Lili Krakowski
Constableville, N.Y.

Be of good courage....

David Hendley on mon 1 sep 03


Yes, there are differences. Iron oxide plus titanium dioxide does not make
rutile. Richard Aerni and others have done extensive research regarding
combinations of iron, titanium, rutile, and illmenite.
There are trace elements in the natural minerals. There are even significant
differences in materials from different suppliers that are all called
"rutile".
One advantage of using natural minerals, rather than refined oxides, is that
they are cheaper. Often the impurities add more character.

David Hendley
david@farmpots.com
http://www.farmpots.com



----- Original Message ----- )
>
> Is there any advantage in using the natural combos? Or would I be ok with
> using iron and titanium, and iron and chrome? Does the natural
combination
> of materials have a specific benefit in the melt?

David Hewitt on tue 2 sep 03


I would agree with David that Rutile is a variable material. Also that
Titanium dioxide is not just TiO2. For example I have the following
analyses from my supplier. Always try and get your supplier to tell you
what they are supplying.

Titanium dioxide
TiO2 >92%
Al2O3 <4%
SiO2 <1%
ZrO2 <1%

Rutile
TiO2 >95%
Fe2O3 <1%
ZrO2 <1%
SiO2 <1%
Al2O3 <.5%
Cr2O3 <.25%

David


In message , David Hendley writes
>Yes, there are differences. Iron oxide plus titanium dioxide does not make
>rutile. Richard Aerni and others have done extensive research regarding
>combinations of iron, titanium, rutile, and illmenite.
>There are trace elements in the natural minerals. There are even significant
>differences in materials from different suppliers that are all called
>"rutile".
>One advantage of using natural minerals, rather than refined oxides, is that
>they are cheaper. Often the impurities add more character.
>
>David Hendley
>david@farmpots.com
>http://www.farmpots.com
>
>
>
>----- Original Message ----- )
>>
>> Is there any advantage in using the natural combos? Or would I be ok with
>> using iron and titanium, and iron and chrome? Does the natural
>combination
>> of materials have a specific benefit in the melt?

--
David Hewitt
David Hewitt Pottery
7 Fairfield Road, Caerleon, Newport,
South Wales, NP18 3DQ.
Tel:- +44 (0) 1633 420647
Fax:- +44 (0) 870 1617274
Web:- http://www.dhpot.demon.co.uk

David Hendley on tue 2 sep 03


I have a friend who owns a paint company. Titanium is very important
to paint makers and he stocks tons of 3 different kinds of titanium
dioxide. Each one is used for a specific purpose.
Earlier this year, I ran out of titanium and asked to borrow a couple
of pounds. The stuff he gave me was like nothing I'd ever used before.
It was exceedingly finely ground and felt almost greasy. It worked
fine in the glaze I put it in.

The titanium dioxide I buy from my supplier, Trinity Ceramic Supply,
is called Tronox Anatase, made by Kerr-McGee.
Anatase is naturally occurring titanium dioxide, free from the iron
contamination present in rutile.
According to Hamer, there are ores that are refined to make
titanium dioxide, anatase, rutile, and brookite.

David Hendley
david@farmpots.com
http://www.farmpots.com



----- Original Message -----
> producers of Titanium Dioxide produce many grades of it with different
> compositions and physical properties.
> There is one I used (Tioxide Tr94) that is zirconium coated and was
> recommended to me by a chemist working for a local producer,
> a U.K-owned company.
>

Edouard Bastarache on tue 2 sep 03


Right David,

producers of Titanium Dioxide produce many grades of it with different
compositions and physical properties.
There is one I used (Tioxide Tr94) that is zirconium coated and was
recommended to me by a chemist working for a local producer,
a U.K-owned company.


Later,




"Ils sont fous ces Quebecois"
Edouard Bastarache
Irreductible Quebecois
Indomitable Quebeker
Sorel-Tracy
Quebec
edouardb@sorel-tracy.qc.ca
http://sorel-tracy.qc.ca/~edouardb/
http://perso.wanadoo.fr/smart2000/index.htm

----- Original Message -----
From: David Hewitt
To:
Sent: Tuesday, September 02, 2003 2:27 AM
Subject: Re: The Pure and Impure (sources of oxides) ????


> I would agree with David that Rutile is a variable material. Also that
> Titanium dioxide is not just TiO2. For example I have the following
> analyses from my supplier. Always try and get your supplier to tell you
> what they are supplying.
>
> Titanium dioxide
> TiO2 >92%
> Al2O3 <4%
> SiO2 <1%
> ZrO2 <1%
>
> Rutile
> TiO2 >95%
> Fe2O3 <1%
> ZrO2 <1%
> SiO2 <1%
> Al2O3 <.5%
> Cr2O3 <.25%
>
> David
>
>
> In message , David Hendley writes
> >Yes, there are differences. Iron oxide plus titanium dioxide does not
make
> >rutile. Richard Aerni and others have done extensive research regarding
> >combinations of iron, titanium, rutile, and illmenite.
> >There are trace elements in the natural minerals. There are even
significant
> >differences in materials from different suppliers that are all called
> >"rutile".
> >One advantage of using natural minerals, rather than refined oxides, is
that
> >they are cheaper. Often the impurities add more character.
> >
> >David Hendley
> >david@farmpots.com
> >http://www.farmpots.com
> >
> >
> >
> >----- Original Message ----- )
> >>
> >> Is there any advantage in using the natural combos? Or would I be ok
with
> >> using iron and titanium, and iron and chrome? Does the natural
> >combination
> >> of materials have a specific benefit in the melt?
>
> --
> David Hewitt
> David Hewitt Pottery
> 7 Fairfield Road, Caerleon, Newport,
> South Wales, NP18 3DQ.
> Tel:- +44 (0) 1633 420647
> Fax:- +44 (0) 870 1617274
> Web:- http://www.dhpot.demon.co.uk
>
>
____________________________________________________________________________
__
> 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.