u/Double_Theory6541

I want to know the method of formation for a couple of rocks I spotted on my hike thru the foothills just north of the Flatirons of Boulder. The first rock with two distinct shades of red, clearly demarcated down the middle. I joked that this rock must have a wild story to tell, but, being a layman, I have no idea lol. Then the second rock I thought looked really cool because of the colours. It makes me wonder how does that even happen?? And then the third photo is a much larger boulder, and I'm curious how big rocks like that get such clear cut striata (or perhaps it's literally just human-made cuts into the rock for the sake of trail maintenance)?