Leave copper beside a dish of vinegar and it will change color. The fumes raise a pale blue-green crust on the metal, and for centuries painters scraped that crust off and ground it into a pigment. The name came through French: vert de Grèce, the green of Greece.
It made a brilliant color, and an unstable one. Painted in oil it could drift toward brown over the years, and painters learned to seal it in glazes to slow that down.
Few colors have so plainly shown their age.
The green on an old roof or a bronze statue is a cousin of the pigment, not the same thing. Weather builds that layer slowly, and once it forms it protects the metal beneath.
Two metals
The kit has one accent, verdigris, for the thing that matters on a screen. Copper is the metal underneath it, and it does a smaller job: labels and ornament. Copper never marks an action, so the two never compete.