Is ink with a liquid solution with fine particles if carbon a pure substance or a mixture?

Ink with a liquid solution containing fine particles of carbon is considered a mixture. This is because it consists of different components—such as water, solvents, dyes, and suspended carbon particles—that can vary in composition and can be separated by physical means. Pure substances, on the other hand, have a uniform and definite composition throughout. Therefore, since ink does not maintain a consistent composition, it qualifies as a mixture.