I found the idea and tutorial for this change purse here:
The tutorial is on the Craft Passion website here:
The tutorial uses ribbon but all of my ribbons were too wide. However, I had a some awesome Emily Strange shoelaces hang around not doing anything so I used them instead and they worked just as well. The tutorial is easy to follow for the most part but I hate working zippers and this coin purse definitely reminded me of that seeing that it is all zipper.
Doing its job.
Completely zipped it forms a pyramid shape.