The video shows a close-up of a yellow substance on a rock. The substance appears to be a type of mold or fungus, and it is growing on the surface of the rock. The rock itself has a rough texture and is a dark color, possibly gray or black. The yellow substance is irregularly shaped and seems to be spreading across the surface of the rock. There is no movement or action in the video; it is simply a still shot of the substance on the rock.