Hey student made a model of a river in a sandbox a pile of sand represents soil and bits of rocks in the riverbed water pouring from 100% river water as it flows downhill which two characteristics are limitations of the students model

Pegmatites are igneous rocks in which the individual minerals are very large. typically, the minerals are all light-colored quartz, feldspar and muscovite. if you were given a black and white photograph of a pegmatite in a quarry (where the rock has been blasted and broken), what physical properties could you use to identify those three minerals in this hypothetical photo? describe each mineral and the specific diagnostic properties. be specific.