When I did my page preparations, I painted this border with sepia colored acrylic paint. Then I painted the entire page with diluted Golden Fluid Acrylic Interference Blue. When the Interference colors are painted on a dark background, there is a color shift when the light hits. That's why you can see bits of blue on the border, which is much more obvious when looking at the pages in person. The white portion of the page has a beautiful satiny sheen from the Interference Blue, though the color shift is most obvious against a dark background. This was a very interesting experiment using a dark background and corresponding color complement in interference paint. I definitely plan to explore more of this!
Because of that color shift, it was difficult to select a color to sketch with, but the combination seemed to unify into a muted reddish-brownish-violet tone, which suited my favorite mix of Private Reserve Velvet Black Ink and Private Reserve Chocolat. I used a waterbrush to wash some of the lines.