The 5 Stages of Clay

Slip, plastic, leather-hard, bone dry, bisque. Know them. Love them. Use them.

Five labeled clay pieces in varying stages: slip, plastic, leather-hard, bone dry, and bisque—illustrating how clay changes during the pottery process

The secret to making great pottery isn’t just artistic talent—it’s knowing your clay. Every piece you make passes through the same five stages, and understanding each one can mean the difference between a perfect pot and a cracked disaster.

Slip: Clay mixed with lots of water—used for attaching pieces together like glue or for slip casting.

Plastic: This is that beautiful, workable stage where you can mold, pinch, throw, and shape with ease. Your clay is alive here.

Leather-Hard: Partially dried, but still workable. This is the time for carving, trimming, adding handles, or refining form without collapse.

Bone Dry: The most fragile stage. It’s fully dry and light in color, but can shatter easily. Don’t touch it more than you need to.

Bisque: This is post-kiln, pre-glaze. The clay has undergone its first firing and is now porous and ready for glaze application.

If you’re ever unsure what stage your piece is in, just ask any of our instructors. They’ve got decades of combined experience and can spot a bone dry vs. leather-hard with one eye closed. 😉

Dan Pearce
Founder | The Clay Hole