While stoneware crocks and crockery objects, such as jugs and butter churns, are valued for their durability and thick-walled construction, they still can develop surface and structural cracks. Stoneware is made from thick clay, but like all clay pottery, it is still porous despite its thickness. Therefore, when you repair a crack in a stoneware crock, you need to use a strong adhesive and make sure it sets properly before you handle the crock again. Super glue (cyanoacrylate adhesive) is the glue of choice for repairing crockery, especially if it is a collection piece or storage container.
Empty the crock of anything that may be stored inside it. Gently clean the cracked interior or exterior surface of the crock with a moist sponge or cloth and gently wipe it dry.
Squeeze super glue into the crack while you move the tube up and down the length and/or width of the crack.
Allow the glue to dry for a minute or two, then wrap elastic fabric or an elastic bandage two or three times around the crock. Tie the ends of the fabric or bandage as tightly as you can, so that the knot is located over the crack and exerts pressure on the glued crack.
Wrap insulated wire three or four times around the bandage or fabric band and crimp or twist the ends together.
Remove the wire and elastic bandage or fabric after 24 hours have passed. Use a razor blade or sharp hobby knife to remove any dried glue visible on the surface of the crock. Refill the crock or return it to its display. Do not cook with, or otherwise heat, a repaired crock, and do not use it for food storage if the crack is inside it.