They've got it on the Spirit Stallion of the Cimarron page too-I don't want to start an edit war or anything, but I do think it needs to be corrected for the sake of BEING correct.

Can someone please change it on the TVtropes website then? Someone is saying hazel there on the hazel eyes page.

though I just answered this and if the mods approve it.. I am posting an eye color chart

In the film he has brown eyes like his model used in real life (Donner) On the site people (like me, mostly ) Like to use more unnatural colors like Green, Amber or grey. But horses can have brown, blue hazel (champagne only) bi eyes (one eye brown, the other blue) sometimes they even have two colors in one eye (like one half of the eye is brown and the other blue)

However, to answer your questing. Spirit's eyes are brown, take a look at the screen shots on the site if you still have doubts.

Horses can have any color of eyes... but Spirit has brown.. hazel only occurs in horses that are born with the champagne gene...
Brown eye colors (dark or light) occur naturally...