I couldn’t remember exactly what Galt was supposed to look like beyond my impression he had dark hair, so I looked it up.
Chestnut brown hair, green eyes, bronzish skin is not so unique. Brazilian model Adriana Lima has that combination, just remembering off the top of my head.
Here is the description from Part III, Chapter 1:
“The light cloth of his shirt seemed to stress, rather than hide, the structure of his figure, his skin was suntanned, his body had the hardness, the guant, tensile strength, the clean precision of a foundry casting, he looked as if he were poured out of metal, but some dimmed, soft-lustered metal, like an aluminum-copper alloy, the color of his skin was blending with the chestnut-brown of his hair, the loose strands of the hair shading from brown to gold in the sun, and his eyes completing the colors, as the one part of the casting left undimmed and harshly lustrous: his eyes were the deep, dark green of light glinting on metal.”
The way she describes him I get the sense that his skin color is unique. I also get the impression that Ayn Rand wanted him to stand out physically in a unique way, sort of like Doc Savage, aka “The Man of Bronze”.
Looking on the web, aluminum-copper can refer to “aluminum bronze”, which according to my Google search varies according to how much copper is in the aluminum. I pictured his skin as somewhat silver, but it could be more brown like Adriana Lima’s.
Here is a picture of Adriana with a tan:
