Remember in pottery nothing is rushed. There is no expiration date on glazes, for the most part, they don't go bad. The only way glazes can go bad is if they get contaminated with dust, dirt, and other unwanted particles that may get in your glaze.

How long do ceramic glazes last?

Indefinitely as long as you keep it hydrated. Rehydrate if it does dry out. 9.

Can glazes expire?

Glazes do not 'go bad' with age but, because different ingredients tend to come out of suspension at different rates, it is critical that the batch or bottle be mixed thoroughly before each application. ... Single firing (glaze applied to greenware) is not recommended with today's glazes.