glowinghand arts = ceramic = local clays = preparation

Materials and equipment:
• sives, screens, coarse and fine • gloves if you want
• hammer
• buckets for storing prepared clay
• notebook and pen for documenting the samples
• ziplock baggies and marker for collecting smaller samples
• safety glasses / face shield

The sample must be fully dry before refinement can begin. Spread your clay out on wooden boards, cement (or concrete), or plaster to dry. The left sample is wet, the right sample dry. A clay will change color from moist to dry stages.

Keep good records of your samples. If you find certain samples are well suited to your needs, you can later return and excavate more material. Keep a small sample labled in a reclosable plastic bag for comparison with all the stages in your refinement. You may also need to compare raw samples when relocating a deposit. These raw samples will give you a visual of the amount and kind of inpurities, sand concentrations, and since the plastic bag should be waterproof, a moist sample displaying the color of the clay as you found it, moist or not.

After drying, the sample must be crushed with a hammer, mallet, or otherwise blunt instrument. Be sure to wear eye protection, and possibly lung protection as well. When the clay is fine, sive through a coarse mesh, like quarter-inch hardware cloth. Discard any rocks and foreign matter, and pulverize the clay to an even finer powder. Sive this through a smaller wire mesh.

Slips are made by adding plenty of water to the powdered clay and mixing and remixing. It could take several days of hydration to create a silky smooth slip. The wet color of the clay is as vibrant as possible in this stage. It gives some indication to the fired clay when clear glossy glaze is applied. Be sure to keep records on your slips as well. The slips can be used to create a terra sigillata to color other clay bodies, but the "fit" needs to be tested or flaking can occur.