The study of automobiles is like an endless sea. It's easy to get lost and not reach the shore. It requires the experience and dexterity of a seasoned navigator to get you on shore. The coachbuilding industry was heavily involved in the construction of the cars back then. Because of the method of fabrication, many of the cars were custom built, much like a horse-drawn carriage or a truck.
Wood was the chief material used during those times to construct the body shell with metal joinaries. Metals such as stainless steel and alloys such as brass were widely used for decorative purposes.
The headlights, windshield framework, horn, and rearview mirrors, among other things, had a shiny metallic appearance. The theme was carried through to the car interiors as well.