Waterglass for protection & paint Waterglass has become my preferred binder in places where it's needed. The chemical name is sodium or potassium silicate. It's an inert mineral compound similar to window glass, but under heat and pressure, it's soluble in water. I get it from a ceramic supplier (it was $9 a gallon when I first published this, now it's $20!). It's clear, viscous, and pours like heavy cream. It dries into a clear, brittle substance that crushes to a fine powder, but it has significant binding power, and is used in some refractory cements, as well as numerous other . . .