Primary minerals form at elevated temperatures from cooling magma during the original solidification of rock or during metamorphism, and they are usually derived from igneous and metamorphic rocks ...

"These are termed the common rock-forming minerals ... their mineral composition. Once their mineral composition changes, the rocks are considered metamorphic, with examples including phyllite ...

The characteristics of the rocks that hold fossils can be as informative as the fossils themselves. There are three main types of rock: igneous rock, metamorphic rock ... causing the minerals that ...