Saving Old Glaze: Rehydrate, Repurpose, Dispose

We’ve all had that sinking feeling when we grab a jar of glaze off the shelf only to realize it’s dried out. What can you do? There are three options: rehydrate, repurpose, or dispose. Let’s talk about the best way to do those things.

Rehydrate

It seems straightforward to just add water to a dried-out glaze, but it takes more than water to make your glaze work correctly again.

What you’ll need:

• Distilled water

• AMACO Gum Solution (Gum Solution helps brushing glazes apply smoothly and adhere to the ware. Gum Solution should be thick and gelatin-like. If it’s watery, it is old, and should be discarded)

• A secondary container that can hold the glaze for mixing.

• An immersion blender or a mixer attachment and hand drill

• Spatula or rubber rib

• Optional: 60 mesh screen

If your glaze is firm but not completely dry, you can remove the glaze to another container with a spatula or rubber rib. Add a small amount of distilled water at a time and use the blender to mix until it’s the consistency of yogurt. Add 1 Tablespoon of Gum Solution to the glaze and blend well for several minutes until smooth. Return the glaze to the original jar. Optionally, sieve the glaze through a screen before returning to the original jar. Sieving helps homogenize the glaze.

Test your glaze on a test tile before using the refreshed glaze or underglaze.

If your glaze or underglaze is completely dry, it will take a little more work. Pour distilled water in the glaze jar, enough to just cover the dry glaze, and close the jar. Let it slake for 24 hours. Check the glaze to see if it’s absorbing the water and showing signs of softening. Add more water as needed and continue to check every 24-48 hours until the glaze has gotten soft all the way through. Use an immersion blender or drill with a mixer attachment to blend well. Add 1 tablespoon of Gum Solution and continue to blend for several more minutes until Gum is thoroughly mixed into the glaze. For best results sieve glaze with screen.

Test your glaze on a small piece or test tile.

Watch Kathy Skaggs demonstrate how to use Gum Solution. 

Not all glazes can be successfully resuscitated. Some glazes, like PC-31 Oatmeal, will peel and crawl when it’s older, but can successfully be layered over other glazes. Some glazes, like PC-1 Saturation Metallic, will crawl after a certain age, no matter how much water or Gum Solution is added to them. Which brings us to the next option ...

Repurpose

Sometimes you may not want to rehydrate a dried-out glaze. Glaze chips are a great way to use dried out glaze. If the glaze is a solid block, place it in a bucket or a freezer bag and smack it with a mallet or brick until it breaks into pieces (wear a dust mask or respirator and eye protection for this activity!). You can also smack the jar a few times to loosen up any dried bits stuck to the inside of the jar or lid.

Use a colander or kitchen screen to sort chips into smallest pieces , medium pieces, and big chunks. The medium sized pieces are best for the following techniques:

• Chips on wet glaze. Apply 3 coats of a stiff glaze (like Amaco Celadons or Satin Mattes) to a piece. While the 3rd coat is still wet sprinkle the glaze chips onto the piece so they will stick. Fire to cone 5.
• Chips in a glaze. You can add chips to a glaze, but they will dissolve if not sintered. To sinter glaze chips, place on a piece of scrap kiln shelf or in a waste bowl and fire to a very low temperature (like cone 010 for mid-range glazes, or lower), just hot enough to fuse the glaze but not so much that the glaze melts. Add to your glaze and you have specks!
• Chips in greenware. This is tricky, and for decorative surfaces only! Roll out a slab of clay. While still wet, use a rolling pin to impress the glaze chips into the surface. Use the slab to create a wall plaque, clock face, or slab dish. When fired, the glaze chips will melt and create divots in the clay, filled with glaze. It’s a fantastic textural technique!

Watch this video to learn how to use dried PC glaze chips to create the magical result shown in the image to the left! 

Discard

Sometimes there’s just no saving a glaze, and then it’s time to say goodbye. Here are our 2 best ways to do it:

• Waste bowl. Throw or hand-build a large, thick bowl and bisque fire it. Place waste glaze (liquid or dry) in the bowl and fire to the recommended range of the glazes. Throw away the bowl (or use it for a garden decoration).
• Household hazardous waste. Contact your local municipality for when they are having a household hazardous waste drop-off event or location. Unfired glaze can be disposed of safely this way.

Never pour glaze in your garden or down storm drains. Avoid putting glaze or clay down the drain, since they can obstruct your plumbing.

So how do you deal with old glazes? If you have an interesting or fun way to use old glaze let us know by sharing it on social media using #howIAmaco

Happy glazing!