Yes, this was the ultimate test on black tile: can I create a gem brooch on black tile? I cannot deny that it was tricky -- I wanted to draw smaller details but the white gel pens are too cumbersome for it.
In the end, I'm pretty happy with the results, even if they are not as fine as the brooches on white paper.
Here is the line-art:
I made the mistake of adding the reflected light of the gem with prismacolor pencil, when I should have used charcoal. Oh well.
Here is a REALLY CLOSE-UP view of the test:
White gel pen, black ink pen, Prismacolor colored pencils, white charcoal pencil over Zentangle® black tile.
Update June 24, 2016: The ebook is here! Also called "the missing link" in Shading Zentangle: http://enioken.com/3dtangle/glowonthedark
Copyright 2016 Eni Oken