Figure 4. This is a close-up of the granite, showing its equigranular texture. The gray minerals are quartz which makes up about 40-50% of the rock. The white mineral is feldspar which makes up another 40-50%. Biotite, the black flakes, and muscovite which does not show well in the photograph, make up 5-10% of the rock. Minor amounts of other minerals also occur in this rock.
Last updated on October 6, 2005