A strong, neutral, high-contrast frame colour.

Matte black eyewear rarely photographs as a flat, even black — the visible grey highlights here are simply the frame's own matte surface catching studio light unevenly.
This matte frame reflects studio light unevenly, so it photographs as a range of greys rather than a flat black — a genuine optical effect of a matte black material rather than a colour-accuracy problem.Photo: “Black Framed Glasses” by Gaurav Dhwaj Khadka, CC BY-SA 4.0, via Wikimedia Commons.
Frames sit directly on the face and carry real visual weight — black is one of the most prominent frame choices.
One of the most versatile frame colours across outfits and occasions.
Provides strong contrast against most eye colours rather than echoing any particular one.
Browse eye coloursReads clearly against most hair colours, including black hair, where it blends more than contrasts.
Browse hair coloursBoth warm and cool metals commonly work, since black itself is neutral. Compare metals.
A black acetate frame absorbs nearly all the light that enters it, so almost everything you see of it is the thin specular sheen on its polished surface. That makes it the darkest object near most faces and the one with the sharpest edges: the eye is drawn to boundaries of high lightness difference, and a black rim draws a line of maximum difference around each eye. On very dark hair it continues an existing dark mass, which is why the same frame can look like a strong graphic outline on one person and a quiet extension of the hairline on another.
The material: Most black frames are dyed cellulose acetate or an injection-moulded plastic; a gloss polish adds bright reflections along the rim, while a matte finish removes them and makes the black look deeper and flatter.
Sources: Cellulose acetate