COE

[Sarah999]

This might sound a tad silly, But what happens if you mix different COE's (for both lamp work and fusing)?
Will anything I make just break?
xxx

[Mary]

Pretty much! Sometimes you'll get cracks, sometimes it falls apart. You can get away with small amounts of close coe's, especially if you're using furnace glass. Furnace glass usually has lead in, which helps prevent problems.