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why not cone 8? ecological concerns

updated wed 12 may 99


Ray Aldridge on tue 11 may 99

At 12:07 PM 5/10/99 EDT, you wrote:
>----------------------------Original message----------------------------
>Ray pleads for Cone 8.
>I would plead for Cone 1. Here in England we can purchase clay which
>matures at Cone 1. It is good stuff.
>We are all, surely, trying to be green. So why this insistence on high
>cones? The implication is that good pots can only be created at high
>That is so obviously wrong thinking.

I would hope no one is thinking this way. I certainly don't. For example,
I think that in many ways Cardew's early work in slipware (lead-glazed
earthenware) is his strongest work.

Of course there is no "best" firing range for pottery. But there are
optimal ranges for specific purposes. I make domestic ware and
functionality is very high on my priority list. Given my technical
resources, vitreous stoneware and porcelain yield the most durable ware for
my personal purposes-- it is very important to me that people use my ware
on a daily basis. Consider that the Chinese in all likelihood did not
progress from earthenware to vitreous ware for esthetic reasons alone.
They were responding to a market that would pay more for ware which was
more durable than earthenware-- a market which justified the higher labor
and fuel costs of high temperature ware.

I'd also like to address the environmental concerns you raise. I must
admit, I always cringe when I hear a potter putting forward the argument
that his practices are more ecologically sound than those of other potters.
This is a terribly slippery slope, because at the bedrock level of this
logic, we must all be prepared to admit that we non-industrial potters are
producing a luxury, not a necessity. We potters may regard making pottery
as a necessity for us, but most of our customers would survive without
access to handmade pottery. Following this logic, we should all give up
our pot-making and be content with the products of industry, which is less
polluting per unit of pottery, due to the efficiencies of large-scale

These matters are never simple. Which is more polluting, a mug made in
earthenware, broken and replaced with another, or one made in stoneware
which does not break? Which is more polluting, a mug fired at ^1 in an
electric kiln powered by a coal-burning plant, or a mug fired to ^8 in a
natural gas kiln?

(I admit to a degree of sensitivity on this subject, since I have a salt
kiln. At regular intervals I am lectured by well-meaning but
poorly-informed persons on the ecological havoc I am wreaking. Nowadays,
of course, I can use this as an opportunity to educate these persons, since
we have actual analyses of salt kiln emissions, which are largely benign.)

Anyway, to return to the subject of the thread, I evidently framed my
question poorly, since several responses missed the point. I understand
that ^10 and ^6 are traditionally the most used glaze ranges in studio
pottery. What I'd like to know is *why*? As I said in my first post, it
seems unlikely that these traditions derived from the practices of Leach
and his disciples, since a number of his published glazes are actually
midrange (he had a lot of cold spots in his kilns, evidently, so he
formulated glazes in the 6-8 Seger range, which corresponds to Orton 5-7,

So what great American potter first enshrined the idea of ^10 as the Holy
Grail of studio pottery? I understand that Binns was one of the first to
make stoneware as an artist-potter. Is he the culprit? Where did Rhodes
get his glazes? I'm just curious.