Walked across this ridge and it was loaded with quartz crystals. You can see the faint veins of white running through the granite. When I got back, I searched the web for “red granite with crystals” and this is what I learned.
What is Pegmatite?
Pegmatites are extreme igneous rocks that form during the final stage of a magma’s crystallization. They are extreme because they contain exceptionally large crystals and they sometimes contain minerals that are rarely found in other types of rocks.
To be called a “pegmatite,” a rock should be composed almost entirely of crystals that are at least one centimeter in diameter. The name “pegmatite” has nothing to do with the mineral composition of the rock.
Most pegmatites have a composition that is similar to granite with abundant quartz, feldspar and mica. These are sometimes called “granite pegmatites” to indicate their mineralogical composition.