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.
Rocks containing crystals are called geodes. (Refer to wikipedia). Also, many rocks, particularly igneous rocks and some sedimentary rocks are crystaline in nature. Granâ¦ite, for example, is typically made up of quartz, mica and feldspar. 8 people found this useful.