The rock is made of granite, an igneous rock that cools slowly underground instead of flowing onto the surface as lava. As it cools, minerals begin to crystalize out of the molten mixture, and one of the last minerals to solidify is quartz. As the huge mass of molten rock cools, it contracts, which can cause fractures. Other fractures may be caused by upsurges of more magma. Since most of the other minerals have already crystallized, the remaining quartz flows into the cracks.

Here, the thick, vertical fracture happened first. Next was the horizontal fracture, with the top part moving to the left, relative to the bottom. That offset the first fracture. Finally, the thinner, diagonal fracture happened. If it had happened before or at the same time as the horizontal crack, it would be offset too.