Puzzle Piece Fusing

So, my friend Laura and I are going to be having a booth at a local autism event next month and I figured I should probably make some additional stock, especially since I've sold a few pieces lately.
The thing that inspired me to try glass fusing was a puzzle piece pendant I saw on a friend, so, given that the puzzle piece has become somewhat of a symbol of the autism community, I thought I would try and make a few puzzle-inspired items to sell.
I've seen a technique where an image is etched onto dichroic glass, leaving just the picture you actually want. It's achieved by choosing a design and making a mask for it. It can be something as simple as a leaf or an initial, or, in my case a puzzle piece. I took my glass fusing teacher's advice and managed to locate a craft punch in the correct shape. I punched out a piece of masking (today it was duck tape - it was all I had, but next time I'll find some better adhesive backed something) and set it on the glass. Then, I applied etching fluid, which, magically, removed the dichroic coating. Once cleaned and topped with a clear capper, it looked like this, below!

Left side - etched puzzle piece, middle is a collage of dichroic bits and the right side is a piece of dichroic that was only etched slightly - we'll see how that one turns out)

I also learned something - the dichroic glass pieces you get from Hobby Lobby don't etch well. I had a coupon so figured it was the cheapest way to try the etching fluid. It etched off the green layer, but not the gold, even after 2 applications. But, it did mask the green, so, I figured I would fire it just to see what it turns out like...