I'm living in central Texas, and we are near our 50th day of triple-digit temperatures in the past 60 days.  My studio is at the front of the house, and keeping it cool enough has been a challenge.  I'm wondering if my clay is reacting to the increased temp in the house (near 80 deg) over a long period of time?  Should I keep it in the refrigerator and take it out a few hours before I plan to use it?  Some that hve been conditioned into blocks and wrapped up have begun to get a light streak around the edge. 

That's weird, but no I wouldn't put it in the refrigerator. My house is around 80 degrees and my clay is fine.

Thanks for the feedback.  I've tossed some of the conditioned clay plugs, and found others with no signs of trouble.  Time to start conditioning more clay.

I seem to remember reading that it can start to cure at high ambient temps, like high 90s to 100s, but I wouldn't have expected that in the 80s which really isn't all that hot.  I guess it might depend on brand.  Some cure at lower temps than others. 

Thanks for replying.  The temp at the ends of the house have often been in the mid 80s - perhaps it is being at that temperature for several months that goofed it up.  I've moved it into the middle of the house to store it until use.

 I am under the impression that clay starts to cure at 90 degrees.

sparklebee:

 I am under the impression that clay starts to cure at 90 degrees.

You are right.  You always seem to be right!  LOL.

I got curious and did some web crawling...  the only definitive statement I could find was that Kato starts curing at 90 degrees F...  and it's a higher-temp curing clay.  I think I'll check on my stash, we've had quite a few hot days this summer!

Thanks for all the comments.  I have a combination of Fimo, Premo, and Kato clays.  Maybe the prolonged exposure to mid 80s heat (several months) did some of them in. 

 They are being stored in a cooler spot until the fall. 

90 degrees, huh? I store most of my clay in the garage and it's gotta hit 90 plenty during the summer, given my garage's western exposure. So, does start-to-cure completely ruin the clay, or can it be salvaged? Not that I'm doing anything with clay these days, but who knows?

You can probably still salvage it but that will vary depending on how soft the clay was when you originally got it.   If it won't condition, you can always try to use a little liquid, etc.  Or go the other way, bake it, and then grate it to use as a mix-in.

once it starts to cure I would not take the time to try and make it workable, as I think that might be a losing battle. we are so fotunate that clay is very affordable - I'd buy fresh if I was going to take the time to make something, then I want nice material.

I finally tossed out all the conditioned plugs (luckily not too many at that time).  The time it would have taken to reuse them didn't seem worth it. 

 Thanks for the feedback.

83rd day of triple-digit temps