I had several problems with these markers
I was disappointed because the ink didn't flow smoothly from the tips of these broad point markers, except for the silver marker which worked just fine. Silver was also the only ink to show a true metallic sheen.
These pens are still usable, if I retrace my lines until the color is uniform, but a better set of metallic markers is manufactured by Prang.
You also get an extra color (green) from Prang, and the Prang set is cheaper.
Both sets of markers are advertised as acid-free (archival quality) but the Prang markers flow more freely and create a broader line. Both sets of pens can be used on dark or light paper.
Prang markers dry within seconds on glossy paper. e.g.photographs. The American Crafts pens smudged on glossy paper after being allowed to dry for a minute.
Maybe I got a bad set of American Crafts metallic markers, but I'm definitely a convert to the Prang brand.