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cone 5-6 clay tests

updated tue 23 jan 01


CINDI ANDERSON on sat 20 jan 01

Looks like I'm not the only one looking for good mid-range clays,
especially on the West Coast. My closest supplier mainly stocks Cone
10, so I just ordered a bunch of Cone 5-6 clays for testing. I have 50
lbs each of the following. Will try some IMCO also when I'm done with

Texas White
Dixon Blend
Cafe Cinco
Buff Red

52 Buff with sand
Buff Sculpture
Dover 60 with sand
Dover white
Electric Brown
Sante Fe
Speckled Buff

You may notice these tend to be on the coarse side. I find B-Mix 5 good
for smooth clay, but in general I need more grog to throw big (not an
expert yet.)

Here's what I have planned for a test. If you have ideas or there's
something you want me to add let me know. Or if you want a description
of any of these.

For each clay:

I will throw at least 25 lbs. Evaluate how it throws, how it wears on
the fingers, how much it can take before it collapses (ie a bowl
overhang), how pleasing the color is wet.

I will throw a couple mugs and a couple casseroles, then extrude handles
and attach. See if it is finicky about attachments.

I will roll slabs and make two tiles (not sure size yet, probably 8"?).
Bend one on purpose to see if it warps during firing.

I will do some carving, to see if it the clay comes out in too big
chunks for good carving.

I will make some test tiles, to evaluate glazes with.

Finally, for those that I like, I will fire at cone 5 and 6, and do an
absorption test at each temperature.

I will also be evaluating color, and strength in greenware state (no
specific test yet, just know that some clays break if you touch them and
others you can drop without breaking.)