Formation
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.
Jasperoid is a rare and peculiar type of metasomatic alteration of rocks. It is formed by extreme alteration of wall rocks within a shear zone which may occur in sediments, andesites, trachytes and basalts.
Composition
Mineral Content
Quartz, Silicon
Clay Minerals, Pyrite, Quartz, Sulfides
Compound Content
Silicon Dioxide
NaCl, CaO, Carbon Dioxide, Magnesium Carbonate, MgO
Transformation
Metamorphism
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Types of Metamorphism
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Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Weathering
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Types of Weathering
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Erosion
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Types of Erosion
Chemical Erosion
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