According to two top Mopar restoration experts, John Grinwald and Jerry Schmidt, I have found the following. Having won numerous Best-of-Show trophies from the Mopar Nationals with partner Rich Berlisk, John has become a Mopar Nationals judge. Grinwald’s "Gold Certified" Bright Green Metallic 1969-1/2 Super Bee went through five years of research and restoration before winning "Best of Show" at the 1994 Mopar Nationals

Black Zinc
A dark, low-gloss finish. Typically found on hood latch, and catch and release assemblies. Schmidt says there is some well-placed misinformation that these parts were phosphate-coated from the factory. "They absolutely were never phosphated from the factory

I would guess that the same process had continued to the 1971 models