Picture 1 shows an immense wall of granite exposed at Yosemite National Park, California. The light color of the rock indicates that it is composed mostly of the minerals quartz and potassium feldspar. Quartz is typically gray to colorless and potassium feldspar is almost always pink colored. The black sheetlike mineral biotite mica is often a minor constituent of granite.
Picture 2 is of Big Rock, a popular rock climbing spot near Riverside, California. Enlarge the picture to see a rock climber in a white tee shirt on the lower-left portion of the rock wall. Most of Big Rock is granite, the light-colored rock, but there are also fragments of gabbro, the dark-colored rock, present within the granite.
Picture 3 is a closeup view of a small sample of granite. Magnify the picture to see the main minerals that comprise granite, quartz, potassium feldspar and biotite mica.
Picture 4 shows individual crystals of potassium feldspar and quartz.
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| Yosemite granite | Big Rock granite | minerals of granite | mineral crystals |
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