All About Rocks

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Rocks are the solid material making up the surface of the Earth.

Minerals are the solid chemical compunds of which Rocks are made.


The Rock CycleAll the moving, shaking, sqeezing, erupting, exploding and eroding that the Earth gets up to keeps rocks changing from one orm to another. (4:28)

Igneous Rocks are Formed Directly from Molten Rock

Igneous Rock FormationPrimer on the origins of Igneous Rocks (4:15)

Classification of Igneous RocksHow igneous rocks are classified, and what each rock tells you about the conditions under which it was formed. (20:16)

Mafic: Magnesium + Ferric (Iron) bearing, therefore dark-colored

Felsic: Feldspar + Silica bearing, therefore light-colored

Metamorphic Rocks are Formed Existing Rocks by Heat and Pressure

How Metamorphic Rocks are Formed  (6:25)

How Metamorphic Rocks are Classified  (14:17)

Sedimentary Rocks are Formed when Mineral and Organic Particles are Depositied at the Surface, and Undergo Cementation

How Sedimentary Rocks are Formed  (6:25)

Sedimentary Rock Identification – A more detailed look at the formation of Sedimentary Rocks, showing us more environments within which it can happen. (15:00)