Tamas

Greg Daly in his book Glazes and Glazing Techniques mention that crushed windows glass (cullet) can be considered a frit, and says "It is similar to borosilicate in its fluxing ability,, but with a different colour response from iron, giving olive greens, brown and blacks, and a strong copper response under reduction." But obviously this is not to achieve the effect Lucy is looking for, but interesting nevertheless.