I've not seen fork details that were standing proud of the surface but that doesn't mean they didn't do it. All the one's I've seen have been negative (into the surface).
The "negative" appearance of the "C", club, etc are likely EDM'd (Electro Discharged Machining) into the surface. Block EDM is commonly used for making plastic injection molds. Milling on the rather hard metal crown would be very time comsuming to get any detail.
Gary Watts
Vancouver, Washington
USA