May be dark or light in color. Often replaces limestone. Does not fizz in acid. These are the coals. There are several types of coal, which you will learn about in a later lab.
Metamorphism causes changes in the texture and mineralogy of other rocks.
The processes of compaction and recrystallization change the texture of rocks during metamorphism. The grains move closer together. The rock becomes more dense. Porosity is reduced. No changes in overall chemistry.