A material that selectively absorbs blue light won't look blue. The colors that are not absorbed are what we see. The observed color is said to be the complement of the absorbed color. For example, dichromate ions absorbs blue light, so their solutions appear orange.
Permanganate ions absorb green light, so permanganate solutions are purple.
Color absorbed Color observed Violet YellowGreen Blue Violet Yellow Blue Orange BlueGreen Red Green Purple YellowGreen Violet Yellow Blue Violet Orange Blue Red Bluegreen Sign up for a free monthly newsletter describing updates, new features, and changes on this site.