The finish of an anchor on a period ship, especially from the Age of Sail, was both functional and, at times, subtly aesthetic.

s were forged from wrought iron. Unpainted anchors would appear dark gray to black, with a slightly rough, hammered texture due to the forging process. Over time, they would naturally develop a protective oxide layer (black rust) that helped prevent deeper corrosion. This gave them a matte, almost soot-black appearance.
For my anchors, if they are originally made from brass, I use a BrassBlak to blacken and dry brush with graphite powder. For wood and 3D printed anchors, a mix of matte black with subtle dry brushing in gunmetal or iron gray gives a realistic iron look. A bit of brown or red ochre can hint at slight rusting, especially near seams or joints.
I think yours looks OK, but it is hard to verify colors as each monitor is calibrated differently.