Freezing Temperatures and clay






We always try to be very careful with your order, taking care to pack it for survival according to the sports season…..Bill Bracker used to say that during football season, UPS will drop kick your package…if it’s basketball season, it’ll be a bounce pass opportunity, or maybe a slam dunk.  Baseball season?  Might be a homerun.  During the winter months, we also consider the cold weather of the season.  We check the temperatures locally and along the likely path of the shipment.  If it falls below the minimum safe temperature, we will hold your shipment.  If you are in a hurry and willing to take a risk, you can authorize shipping in the risky temperature zone. Please don’t ask us to ship your order in the “Not Suggested” zone.  We’ll do it if you ask, but we won’t like it.



Minimum Safe temp

Risky Temp

Not Suggested




19º and under




23º and under




21º and under

Wax Resist & other liquids



27º and under




29º and under

****UPDATE 12.20.22:  The Ehlenfeldt Clause***** To be absolutely 100% clear, your order will be completely processed and ready to ship.  This means we will charge your credit card, or capture paypal funds, and tracking information will be created as if it were shipping out immediately, but we will hold it on your behalf for the protection of the product that you now own but is being stored in our warehouse.  (We unfortunatley have to go to extra lengths to make this clear following a customer in New Hampshire who complained after agreeing to honor our judgment and appreciating the input regarding safe shipping of some Lustres when the temperatures between Kansas and New Hampshire were ranging from -6 to a high of 30 during the transit time.)  Please note if you decide you do not want to wait any longer, your order will be treated as a return, not a cancellation and will be subject to the return policy.

So what happens if these things freeze?

Clay is not harmed by freezing, but it does affect its usabiliity and workability.  The water in the clay is what freezes, and those water molecules form ice crystals and that disrupts the homegenous structure of all the platelets.  When the clay, or rather when the ice crystals thaw, the resulting consistency of the clay may be more like pudding than a typical block of clay.  But the clay is fine, it just needs some TLC.  Open the bag, let some of the water evaporate into the surrounding air for a few hours, then wedge the clay to remove air pockets left by the thawing of the ice crystals.

Casting Slip is not harmed by freezing, but the expansion of the product might cause packaging to burst.  We package our casting slip into a plastic bag-lined box.  We advise you to remove the plastic bag from the box and put it inside another bag, just in case the bag was perforated by the freezing

Glazes and underglazes are also not harmed by freezing, but share the same concern regarding packaging.  Freezing can also cause the gum in the glaze to break down.  This might result in reduced brushability and it might also start to smell bad several months after the freezing incident.

Wax Resist, Latex, Sodium Silicate, Darvan, and other liquids are destroyed by freezing.

Lustres and Metallics – well we actually don’t kow for sure if freezing renders these completely unusable, but frankly they are expensive enough that we wouldn’t really want to risk it.  We also believe that the medium that the materials are suspended is what would be sensitive to freezing and if it does freeze, probably you will not be able to apply the gold, platinum, mother of pearl. etc.