<span>is a 1922 agreement among seven U.S. states in the basin of the Colorado River in the American Southwest governing the allocation of the water rights to the river's water among the parties of the interstate compact</span>
Answer:
The color is considered dark if the rock appears as a dark gray to black (pyroxenes, the amphibole Hornblende, the mostly Ca-plagioclases near Anorthite, and Biotite mica. Density is a property that is proportional to the composition of the rock. The higher the amount of silica (felsic) the less dense the rock will be.
Explanation:
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