Have you ever been in a time crunch when completing clay projects with your students? When doing clay projects in the art classroom, the end of the year or a holiday break is always knocking on your door. If you still want to use pottery glaze with your students you might be wondering how the glaze will look on greenware or unfired ceramic pieces.
What is greenware pottery?
This refers to clay pieces that have not gone in the kiln for a bisque fire.
3 Stages Of Clay
- Plastic: still moldable and wet clay
- Leather-hard: Normally 1-3 days after the project has started drying. The clay will feel cool to the touch and it is not ready for the kiln. You can still sculpt, trim or use slip in this stage.
- Bone Dry: This is when there is no moisture left in the clay. If you were doing a bisque fire you would want your clay pieces to be completely bone dry.
How to check that you don’t have moisture left in the clay?
An easy way to check is to see make sure that the clay does not feel cold to the touch. If it feels cold, then there still could be water in the clay and you would not want to fire it. If there is still moisture in the clay then your pieces could explode in the kiln.
Yes, you can glaze greenware pottery and still have the project turn out well.
Normally when doing clay projects with children we fire their projects after being built. However, there have been times when a student is ready to glaze but we could get around to firing their project.
Pros to glazing greenware
- Time, time, time. This method is all about saving you the time of loading and unloading your bisque fire.
- You would also save money on the resources used to fire the kiln because you are eliminating one firing.
The biggest cons to glazing greenware pieces with children
- The number one issue is that dried clay projects are not nearly as durable as bisque-fired projects. Chances are higher of a student breaking their clay projects while glazing.
- Cracking is more likely to occur.
- Colors may not come out as well.
Clay lessons that are sturdy in nature may work better for this glazing technique. For example, we have had no issues with older elementary students glazing coil pots that were not bisque-fired.
The details in this clay elephant or animal lesson may make this project a tough one to try to glaze without firing.
What glazes work better with kids on greenware?
We have had students use Mayco Stroke and Coat and get pretty vibrant colors.
You can read more of our tips for using clay glazes with children here.
You can see how this pinch pot monster was glazed without a bisque firing. We had to be very careful when glazing the details to make sure not to break them.
But the colors really turned out as well as they would have if the project was bisque fired. If you are in a more advanced ceramic setting, air-brush or spray on clay glaze to greenware ceramics could work pretty well.
When would you not want to glaze greenware?
I would not try this with kids if there are a lot of tiny details sticking off. Also, you can not dip or use tongs very easily.
Don’t even want to glaze your clay projects? Check out these 8 glaze alternatives you can use with your students today!