The moss is dark green, and right now it looks like little leaves that are rolled up tight. The lichen is more of a gray-green color, near the moss. Moss is a plant, and lichen is (usually) part fungus and part algae (algae is basically a plant). The fungus and the algae share resources together: the fungus makes the structure, while the algae does photosynthesis and shares glucose with the fungus. What a brilliant arrangement!
I am a science and math teacher, and a former Field Instructor/Naturalist at Walden West Outdoor School. I've also worked at outdoor schools called Foothill Horizons and Rancho Alegre, with additional brief stints at Web Of Life, Sierra Nevada Journeys, and Walker Creek Ranch.