It’s in the nature of a broken fragment to have along its edge at least one vertex. An axis can be drawn from it to give the shape a spine. I like to locate the vertex of a shard before I do anything with it. For the EYE SITES tiles I drew an arc with a compass putting one leg on the vertex and the other on a found irregularity along an upper edge. The axis connecting the vertex to the center of the arc is emphasized with a heavy graphite pencil line that rubbing will soften. After doing this with all the fragments I reassemble the tile and for the first time sense its inner structure. By pairing tiles that attract and excite each other a panel consisting of multiple tiles begins to form.