This is a piece I just finished. It was a bit challenging to get the finished look I was after. I did the first two firings as a crackle project with the yellow and brown veining. It seemed a little boring to leave like that so after the second fuse with clear sheet glass on the top I then sifted orange and blue powder frit over a leaf stencil I created. I full fused that but the blue came out to light. So I decided to add a dark brown line of liquid glass made of gel and powder around the leaf and around the outside edge. I then full fused again. The blue still was not to my liking so I made liquid glass again and applied using a squirt bottle in a thicker layer. Now I fused again. Finally I found that to be acceptable. The leaf popped out more and so did the crackle in the leaf. In person the depth of the layers is more evident.
If you are interested in the crackle effect Bob Leatherbarrow’s book is a good reference for that.