glazing info

How Did Those Crystals Get There?

A ceramic glaze is essentially layer of glass fired onto the surface of a clay body. How, then - if window glass doesn’t have crystals - have magical shapes bloomed on the surface of these pots? Through the use of artifice and science - and after much experimentation!

In nature, crystals often form when a solution cools. Salt and snowflakes are examples of crystals that formed during cooling. Not all solutions make crystals when they cool, however - and glass is one that doesn’t. (In fact, although it appears solid and homogenous, window glass is actually a very slow-moving liquid.) The secret to generating crystals in the glass fired onto the surface of these pots is in the glaze recipe, and in the manipulation of the cooling process.

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