restoring hood latch parts

I don't think black zinc or whatever they call it is technically correct. It is more of a brownish coating. I believe Jules was gearing up to replate them.

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

I would like to know how they went from black to brown. I think you will find that it is actually yellow zinc plating, which can go from a pale yellow to gold to dark brown.

NOS hood latch.

NOS Safety Latch.

Snoopy you may be right or not.
I have been at it now for over 10 months trying to get that color.
Here are the mojor problems I came across. After having spoken to
at least 3 experts ( men that have 25 years or more experience with plating),
they all agree that the brownish hue comes from an additive used in the black
zinc chromate tank. The item is plated yellow or clear zinc at first and then dipped in the
"black" zinc chromate tank. The problem is that this additive has long been
banned. They gave me the name but I couldn't pronounce it for the life of me.
It now boils down to what they call " artistic development". In other words
I have to locate a plater that is willing to invest moocho time and money doing
many samples with other chemicals. In some cases I have been given barely close results
but close is not good enough for me right now. The other problem is client perception.
These NOS latch pictures are of parts that are 30-40 years old and have oxidized
since day one. No one can be sure that they looked like that coming out of the tank.
Some are dark and some are lite. I am still waiting on samples and hope to get things
underway soon. I already have invested much on the rest of the parts to do these parts correctly
so I cannot stop now.
Jules

Jules,
The finish looks a lot like the finish on the Cuda tail light housings.
Do you think that when they dipped the yellow zinc part into the black process tank, it took on the brown coloring or did it come out black and change to brown through oxidation?

I am just guessing at this point but some experts believe that it is oxidized black.
Keep in mind that a very short dip in the black tank yields a color which will tarnish much faster.
I have some black zinc parts that have tarnished to lite black.
So who knows for sure.
Jules