Getting the most from Amaco Kiln Ice

Based on traditional East Asian Guan or “Snowflake” glazes, Kiln Ice are a crackle glaze unlike anything else you can buy! The crackles in Kiln Ice glazes are dramatic and eye-catching, layered like individual flakes of snow.

Kiln Ice glazes are lovely on dark clays, or over an underglaze. Darker base colors enhance the layered crackle pattern. KI-21 Winter Glass macro on Dark Chocolate clay.

Kiln Ice glazes are also beautiful on white or light-colored clays, so don’t feel like you can only use them on dark clay. KI-21 Winter Glass on A-Mix White Stoneware.

Kiln Ice glazes are tested and certified as food-safe by US FDA standards, but due to the highly crazed surface these glazes are recommended for decorative forms or non-food contact surfaces. Use them on decorative tiles, on the outsides of bowls or mugs, on sculptural pieces, candle votives, etc. 

Here are my tips for getting the best results:

CLAY

• Use manganese-free clays. Most black, charcoal, or dark brown clays have manganese unless they specifically say they are manganese-free. Kiln Ice glaze will crawl excessively on manganese clays. Amaco Dark Chocolate and Milk Chocolate Premium Clays are manganese-free and look amazing with Kiln Ice glazes! 

• Use Kiln Ice over an underglaze for an extra layer of color and translucency. Test with your chosen underglaze color and Kiln Ice glaze for compatibility. I love using V-361 Jet Black to show off the crackle pattern. 

• Use hand-built or thrown forms. Avoid slip-cast ware. The compression of the crackle glaze can cause the slip-cast ware to break. Ware should be an even thickness throughout. Even with handbuilt or thrown pieces, dunting (cracking through the clay) can occur.

• Kiln Ice look best on relatively smooth pieces. The thick nature of Kiln Ice covers up most surface texture.

APPLYING GLAZE

• Test Kiln Ice on your selected clay body to see how much is needed for the best crackle. 4 coats is recommended. Kiln Ice glazes are thick. If you add water, you may need more coats to get the best crackle.

• Wrap the glaze around edges and rims to give the glaze something to grab onto. The surface tension of wrapping around edges helps the glaze create the layered crackle.

• For functional pieces use Kiln Ice on non-food surfaces (like the outsides of mugs or bowls) and use a clear gloss glaze like HF-9 Zinc-Free Clear for all food surfaces. Avoid using matte or white glazes as liners for Kiln Ice as they can create tension that may crack your ware.

• Kiln Ice can be applied in smaller areas as an accent on pieces. Since it doesn’t run, you can be selective about its placement. 

• Kiln Ice glazes are not meant to be layered. When layered with other glazes they lose the crackle and run excessively.

AFTER FIRING

• The crackle forms as the glaze cools and can take up to 48 hours after firing to expect the crackle to fully develop. Expect the pinging to be loud!

Enjoy using Amaco Kiln Ice glazes, and share your creations with us using #HowIAmaco

Happy glazing!