Lettering on black is an incredible technique but it is also hard to create contrast as the darkness of the medium absorbs colour. These metallic markers are great for that purpose, not only because the colours are beautiful, but also cause the tip is a thin brush! So easy to use and the result is beautiful. Check the video I did below and see for yourself the brightness of the metallic ink! My fave is copper!
PRO TIP: I use these markers a lot specially when wrapping gifts... that's right! I just use plain black paper and use my metallic markers to doodle away! the result is so unique and pretty you'll love it!