Formation
Mineral Content
Compound Content
Metamorphism
Types of Metamorphism
Weathering
Types of Weathering
Erosion
Types of Erosion
Anthracite forms from the accumulation of plant debris in a swamp environment. When plant debris dies and falls into the swamp, the standing water of the swamp protects it from decay.
Calcite, Clay, Clay Minerals
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
Burial Metamorphism, Contact Metamorphism, Regional Metamorphism
Chert forms when microcrystals of silicon dioxide grow within soft sediments that become limestone or chalk. The chert formation can be either of chemical or biological origin.