Richard Aerni on wed 2 apr 97
Hello again everyone,
I don't know if I'm writing to myself here, or if there are others like
me staying home from NCECA who will read this.
I've been pursuing some leads on my rutile problem since my post about it
yesterday. Got through to some folks at some of the bigger companies,
who've been incredibly helpful and generous with their time. I had a
long talk with one of the engineers of TAM's Process Engineering Group in
Niagara Falls, NY, a major supplier of rutile to the USA. They used to
sell Sierra Leonian rutile, but stopped when the mine did close in 1995
due to political upheaval. When or whether it will reopen is not clear;
I suspect this is similar to the situation with the cobalt works in that
continent as well. At any rate, he said that the Sierra Leonian rutile
was of a very great purity; the others now available are more impure, and
to him, more unsatisfactory. He said that I was not the first client to
call him with tales of woe about the new rutile adversely affecting
products.
TAM carries two kinds of fine mesh rutile--Dark Rutile, or Ruflux 61
(product number 54430), and Ceramic Grade rutile. Both are the same
mineral, the difference being that the Ceramic Grade has been calcined.
I asked what difference it made to calcine it, and got an answer that was
beyond my current understanding of industrial mineralogical chemistry. I
got the feeling that either would work fine for my purposes. TAM's
rutile is currently a blending of rutiles from two different locales (I
was told it was proprietary info as to the where's and whys of it, so I
won't repeat his locations), each one with different formulas (I gather
this is for much the same reasons we include a variety of ingredients
into our clay bodies and glaze recipes). They are sending me samples of
both for my testing. Here is a tip the engineer gave me regarding
samples from companies. He suggested I talk to the customer rep and ask
for a sample from their current lot, and get the lot number. His
company, and I would suppose most others, keep a bag in the office for
sending out samples, but by the time they reach the bottom of it, they
may be months removed from what they are currently milling and selling.
Thus ask for a sample from the current lot. He also said they would
earmark a pallet of my lot # and hold it, so that if my tests worked,
they would ship from that pallet. What I know is, if I find a batch that
works for me, I'll order a thousand pounds so this will be one less
problem I'll have in the future.
At any rate, a large proportion of the rutile now available comes from
Australia, it seems. Rutile is a part of granite and other igneous
rocks, and as they are degraded, particularly around the seashore
formations, they are washed ashore. The wave action along the beach acts
as a kind of screen mechanism, dropping the heavier particles closer to
the sea and carrying the finer further along. As seas recede or encroach
throughout geological time, they leave running deposits that can stretch
for long distances. In western Australia these deposits can be 30 km in
width. There are now six major titania mining companies in Australia
(down from 30 or so a couple of decades ago). The one that TAM buys from
is called CRL (a subsidiary of RGC--a US company). Seems there is a lot
of buying and selling of these companies going on. If you're interested
in a much more detailed account of titania/rutile mining and processing,
go to http://www.mineralswa.asn.au/info2/titanium.html . I came across
literally hundreds of websites dealing with rutile in an Altavista search
yesterday--it will take time to deal with them.
So, the upshot of all this is I've got lots of leads and lots of info to
process. Also roughly twenty different rutile samples to test. A lot of
work to do. The small light at the end of the tunnel may be that at my
old supplier (the one that used to have the good stuff), they've found a
small drum with about thirty pounds of old rutile in it--a remnant of a
torn bag of years ago. They're sending me a sample of it for testing,
and if it works, I've got a bit of breathing room until I can test and
develop a satisfactory substitute. Then again, if it ain't the right
stuff...
I guess the moral of this long tale is to test, test, test, and stay up
with your suppliers. But in truth, in a one person shop, with limited
output and limited income, that is hard to do, unless you're committed to
nothing else but your clay work (in which case you'll probably be
eligible to be committed in a few years). And it will always be
something...in my limited time in clay, I've seen the demise of numerous
spars, clays, and glaze ingredients upon which studio potters have
depended. Most of us have survived despite it all. My solution will be
when I find something that works, buy it in quantity. I've still got
some room in the garage and the basement for a few more pallets.
Well, that's all for now. If you've stuck with this this far, you've got
to get a life! (my excuse is I'm in with a sick child, and the
alternative is taxes and accounting).
Take care,
Richard Aerni
Bloomfield, NY rcaerni@servtech.com
Brad S. Reitz on wed 2 apr 97
Richard,
I suspect the information about rutile will help numerous people on this list.
I had no idea the formulas and differences were so great. You now have made me
wonder about the differences I have noticed in both color and texture. I
learned the hard way about granular! I hope you'll keep us posted. Is there
any quick way to tell if it has been calcined?? Do we all suspect our recipes
are for un calcined?? Now I'm really beginning to wonder and have a new
suspect for those pesky failed glaze tests. Any insight?
James Dapogny on fri 11 apr 97
Hi Everyone and Richard,
I am not knowledgeable enough to be able to reply to the rutile problem (I
am listening with great interest), but I wanted to pass on a couple of
things that are related.
1) In a workshop last year, Robin Hopper referred to rutile problems,
mentioning that he was aware of big discrepancies in rutile; so he might
have some answers.
2) If you are looking for a reliable rutile blue glaze, I have one that
uses titanium (pure form of rutile, of course) and is very nice. It is:
SEGAR cone 9/10 reduction
potash feldspar 504
flint 324
ball clay 156
whiting 216
_________
1200
black fe 4%
titanium 4%
It comes out as a classic blue (thick), rust (thinner) glaze and I have
found it to be very reliable.
Also, Richard, I've wanted to thank you for ages for the strontium. I
haven't yet tried it because I began substituting the above glaze for the
one in question. But sometime I will play around with it. Anyway thanks
so much!
--Gail Dapogny in Ann Arbor (20s and expecting snow)
Richard Aerni on tue 16 sep 03
To the list...rutile yet again...
If it helps anyone, here is a copy of a post concerning rutile that I made
to clayart in 1997. Be warned, others may follow!
Richard
----------------------------Original message----------------------------
Hello again everyone,
I don't know if I'm writing to myself here, or if there are others like
me staying home from NCECA who will read this.
I've been pursuing some leads on my rutile problem since my post about it
yesterday. Got through to some folks at some of the bigger companies,
who've been incredibly helpful and generous with their time. I had a
long talk with one of the engineers of TAM's Process Engineering Group in
Niagara Falls, NY, a major supplier of rutile to the USA. They used to
sell Sierra Leonian rutile, but stopped when the mine did close in 1995
due to political upheaval. When or whether it will reopen is not clear;
I suspect this is similar to the situation with the cobalt works in that
continent as well. At any rate, he said that the Sierra Leonian rutile
was of a very great purity; the others now available are more impure, and
to him, more unsatisfactory. He said that I was not the first client to
call him with tales of woe about the new rutile adversely affecting
products.
TAM carries two kinds of fine mesh rutile--Dark Rutile, or Ruflux 61
(product number 54430), and Ceramic Grade rutile. Both are the same
mineral, the difference being that the Ceramic Grade has been calcined.
I asked what difference it made to calcine it, and got an answer that was
beyond my current understanding of industrial mineralogical chemistry. I
got the feeling that either would work fine for my purposes. TAM's
rutile is currently a blending of rutiles from two different locales (I
was told it was proprietary info as to the where's and whys of it, so I
won't repeat his locations), each one with different formulas (I gather
this is for much the same reasons we include a variety of ingredients
into our clay bodies and glaze recipes). They are sending me samples of
both for my testing. Here is a tip the engineer gave me regarding
samples from companies. He suggested I talk to the customer rep and ask
for a sample from their current lot, and get the lot number. His
company, and I would suppose most others, keep a bag in the office for
sending out samples, but by the time they reach the bottom of it, they
may be months removed from what they are currently milling and selling.
Thus ask for a sample from the current lot. He also said they would
earmark a pallet of my lot # and hold it, so that if my tests worked,
they would ship from that pallet. What I know is, if I find a batch that
works for me, I'll order a thousand pounds so this will be one less
problem I'll have in the future.
At any rate, a large proportion of the rutile now available comes from
Australia, it seems. Rutile is a part of granite and other igneous
rocks, and as they are degraded, particularly around the seashore
formations, they are washed ashore. The wave action along the beach acts
as a kind of screen mechanism, dropping the heavier particles closer to
the sea and carrying the finer further along. As seas recede or encroach
throughout geological time, they leave running deposits that can stretch
for long distances. In western Australia these deposits can be 30 km in
width. There are now six major titania mining companies in Australia
(down from 30 or so a couple of decades ago). The one that TAM buys from
is called CRL (a subsidiary of RGC--a US company). Seems there is a lot
of buying and selling of these companies going on. If you're interested
in a much more detailed account of titania/rutile mining and processing,
go to http://www.mineralswa.asn.au/info2/titanium.html . I came across
literally hundreds of websites dealing with rutile in an Altavista search
yesterday--it will take time to deal with them.
So, the upshot of all this is I've got lots of leads and lots of info to
process. Also roughly twenty different rutile samples to test. A lot of
work to do. The small light at the end of the tunnel may be that at my
old supplier (the one that used to have the good stuff), they've found a
small drum with about thirty pounds of old rutile in it--a remnant of a
torn bag of years ago. They're sending me a sample of it for testing,
and if it works, I've got a bit of breathing room until I can test and
develop a satisfactory substitute. Then again, if it ain't the right
stuff...
I guess the moral of this long tale is to test, test, test, and stay up
with your suppliers. But in truth, in a one person shop, with limited
output and limited income, that is hard to do, unless you're committed to
nothing else but your clay work (in which case you'll probably be
eligible to be committed in a few years). And it will always be
something...in my limited time in clay, I've seen the demise of numerous
spars, clays, and glaze ingredients upon which studio potters have
depended. Most of us have survived despite it all. My solution will be
when I find something that works, buy it in quantity. I've still got
some room in the garage and the basement for a few more pallets.
Well, that's all for now. If you've stuck with this this far, you've got
to get a life! (my excuse is I'm in with a sick child, and the
alternative is taxes and accounting).
Take care,
Richard Aerni
Bloomfield
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