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Have you ever had a glaze that kept settling to the bottom of your bucket? This is a common problem and may result in firing problems. When a glaze settles out, some of the heavier components of the glaze settle to the bottom of the container. If you try to use this glaze without thoroughly remixing you will be applying a glaze with key ingredients missing. A glaze stays in suspension due to the presence of various types of clays, such as bentonite, and/or gums, such as CMC. One common cause of settling out is the addition of too much water to the glaze, which dilutes the effect of the suspending agents and allows some of the glaze ingredients to settle out. Another possibility is the growth of bacteria which will consume an organic gum, such as CMC, and will lead to loss of suspension. To prevent bacteria growth do no return used glaze, which has been poured out of the original container, back into the original container. Also do not introduce possibly contaminated objects, such as brushes, into the original container. Storing glaze in a hot or sunny environment may also encourage bacteria growth. Freezing can also destroy the action of CMC. And glaze ingredients such as frits, nepheline syenite, soda feldspar and other slightly soluble materials slowly release sodium ions which can deactivate the suspension agent, making it ineffective.