Great photos. I remember following your Spot track and speculating where you were going next.
Regarding that rock with the lichen on it, it looks like it's origin is volcanic basalt, probably metamorphized to make it denser and harder than average. Hard to imagine now, but all the granite we see exposed today was formed deep beneath the ground under extreme heat and pressure. For most of the High Sierra, the rock above the granite formed by volcanic flow after volcanic flow. Most of the volcanic material became weathered much more easily than granite, and then eroded away as the mountains uplifted and glaciers carved away at it. That's why we see remnants of volcanic rock types in various places, and always on top of the granite (unless there was dramatic folding or faulting in the area). Wherever you see the volcanics up above, you'll probably see more flowers and vegetation on the slopes and in the valley below. You probably know all this already, but someone else might appreciate a little geology primer. I'm not a geologist but this comes up all the time engineering dams in the Sierras.
