The granite shows alteration by hydrothermal fluids by breaking down into a crumbly brownish granite. The huge aggregations of crystals occur in those. On the mountain in the background of the first picture , Liberty Bell , most of the granite is unaltered on the huge east face which is on the left edge of the first photo. There are small very dispersed vugs with small crystals in that granite but very high on the east face is the Hercan roofs area , an area of huge overhangs. The overhangs are made because the altered granite is softer and has weathered away leaving the hard unaltered granite as the overhang. I climbed that face in winter and the Hercan roofs were my lead. Rotten rock, cold and snow and diminishing daylight spurred my progress. In desperation to make time I put my hands in the crystal vugs , made a fist so the crystals dug in and swung from vug to vug up the overhang. A little bloody but very secure. There were so many vugs that I skipped most of them. Some of the vugs on a nearby ridge are square and can fit houses in them and the biggest about 600 feet off the ground is about 600 foot high and about as wide. No collector has ever found a crystal in any of the gigantic vugs they all frosted out thousands of years ago but they are exciting to be in since they are huge and pretty much square , very very unusual. They are locally called wookie tubs , they got that name when we were collecting there about the time of the first star wars movie and will still be there in a thousand years when the movie franchise ends.