text: Andesitic magma is an intermediate magma and is approximately evenly dispersed regarding iron, magnesium, calcium, sodium, and potassium. The silica composition of andesitic magma ranges from 55 - 65 wt.%. It forms in temperatures ranging from approximately 1470 °F to 1830 °F.  Andesitic magma has an intermediate viscosity and volatiles content. It forms minerals such as plagioclase feldspar, mica, and amphibole.