That is, if you observe the spectrum of a star and can determine the wavelength where the emission peaks (Î»max), you can calculate that starâs temperature. Here is another copy of the plot that we studied in Lesson 3: Figure 4.1: Two-dimensional plot of the spectrum of a blackbody with different temperatures.
Igneous rocks usually contain the most crystals. The longer it takes the magma to cool, the larger the crystals.
A common rock-forming mineral found in felsic igneous rocks, pegmatites and metamorphic rocks, muscovite is the lightest-colored member of the mica mineral group. Micas are a group of sheet silicate minerals distinguished by their perfect single cleavage.his cleavage allows mica minerals to be easily split into thin parallel sheets. In India and Eastern Europe, muscovite can be found in crystals large-enough to be split into sheets to be used as windowpanes.