I love stuff like this. The article mentions Werner’s Nomenclature of Colour which is a marvel. There is a wonderful Thames and Hudson book, Nature’s Palette, which includes Werner’s Nomenclature and expands on it by discussing how the nomenclature was produced, has illustrations of the reference plants and animals Werner used, etc.

https://amzn.eu/d/0injz69N

It makes for a great gift for an aspiring artist interested in natural themes, I think. Particularly when paired with Taschen’s The Art and Science of Ernst Haeckel which is a similarly mesmerising historical reference:

https://amzn.eu/d/0hZ4IE2i

Is there a way to determine how true to original color they are now?

Motorola uses pantone colors but I think the color is the least of their issues: https://m.gsmarena.com/motorola_signature_27_5g-14955.php

It turns out after a second of searching it's not really about that. What it is about I do not know how it helps the phone.

https://www.pantone.com/na/en-us/color-systems/pantone-color...

I'm impressed that the colours are still so vibrant, based on the photos from the books. Some extra context around restoration of of the book would help.