I love the sound of that! It calls to mind a piece of an ancient manuscript or pottery. But no, it's a zentangle fragment, and it's part of Henrike Bratz' guest Diva challenge this week. There is a wonderful explanation with lots of pictures on Henrike's blog here.
For the challenge we are to use both the Lisbon fragment and the tangle Diva Dance. I have only barely worked with the fragments and reticulae concept, so this challenge is a good opportunity to delve a little deeper. Here's my first go. The fragment is in a curved grid so it's a little awkward.