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.
Rockhound. The two major properties used to classify igneous rock are: Crystal Size/Texture --Small crystals are indicative of rapid above ground cooling of lava into what is classified as extrusive igneous rock such as basalt, obsidian, or rhyolite.ockhound. The two major properties used to classify igneous rock are: Crystal Size/Texture --Small crystals are indicative of rapid above ground cooling of lava into what is classified as extrusive igneous rock such as basalt, obsidian, or rhyolite.