Yes, Another Scott 78 Color Post

I scanned these 3 Scott 78 variety stamps side-by-side. To my eyes the one on the left is grey as I can't pick up any lilac tones in it at all so I'm guessing 78b. The middle one I think has a very light lilac tinge to it, so a 78 or possibly a 78a. But I am at a loss when it comes to the third. I can make out no lilac in it at all. So, please help. How should I classify it? Is there such a thing as a very dark grey?

I've seen the color charts for these in earlier posts so I know there is some real expertise here on this issue!

I would suggest getting a Pantone color guide, an ottlite lamp, and a copy of philatelic book of secrets. I don't think anyone can weigh in on any color variety using a digital scan and a backlit monitor.

The color names for the 70/78 stamps are awful. I tend to think that almost all the color has faded out of these stamps over the last 150 years. The only 70/78 stamps that anyone would actually describe as "lilac" (or anything other than a gray shade) are some of the proofs. As for your stamps, I'd guess they are all 78a based on your scans. The middle one is toned which throws off the color pretty significantly. I really like the color and impression (and cancel) of the stamp on the right.

IMO, the stamp on the right is likely dark gray lilac or dark gray. Neither is a listed Scott shade, but I have both in my reference collection. IMO, it isn't nearly "black" enough to have a shot a 78c (blackish violet), which I also have and is a very distinct (literally "black") shade. BTW, I also have a PF-certified "very dark lilac" which IMO is really the dark gray lilac shade (there's virtually no lilac in it - mostly dark gray, so really should be called dark lilac gray, not dark gray lilac...)

The Scott 70's/78's are essentially a continuous spectrum of color IMO, and delineating where one Scott sub-number begins and another ends can be pretty subjective. There are paper & impression differences that help identify 70 vs 78, but the shades themselves are typically all over the place. Adding to the problem is the fact that the inks not particularly stable, so they shift in color over time making ID's even more difficult.