Grammar check: to hyphenate or not to hyphenate?

For context, the use of magic in this story world bleaches your hair to a very specific metallic silver (which I guess isn't really bleaching but whatever), and the more magic you have and use, the larger the proportion of your hair goes from its natural colour to silver.

My question is whether whether it should be "mage silver" or "mage-silver" in the following sentence:

[Only the fact that almost two-thirds of his hair was mage(-)silver revealed the depth of his power as a five-star mage who used his abilities to the fullest on a daily basis.]

I'm leaning towards hyphenating, because if I inverted the phrase, "mage-silver hair" looks correct over "mage silver hair" but something about the inversion makes it look weird.

"Mage-silver" seems right to my eye. "Hair" is being modified by both "mage" and "silver," so I'm pretty sure that'd qualify "mage-silver" as a compound modifier, which are usually hyphenated.

But I've always hated grammar lessons, so my recollection could be a bit rusty.

The problem is that I can't find anything specific for compound modifiers that are placed after the noun, as in this case. Most of the examples I've found are "[Compound Modifier] [Noun]". Here are some examples:

Personally, I prefer "mage silver" without the hyphen, specifically because it comes after the noun. Like, replace it with a non-unique color:

"his hair was flamingo pink" vs "his hair was flamingo-pink"


"his hair was sky blue" vs "his hair was sky-blue"

I'm thinking "mage" modifies "silver", which in turn modifies "hair". So maybe it's not even a compound modifier? Either way I think it looks better without the hyphen.

"Mage-silver" when using it as an adjective, "mage silver" when refering to the colour itself.

Hmm, you have me convinced. No hyphen it is! Thanks :)