What are rocks and minerals?  All rocks are made of minerals  A mineral is a pure substance that forms naturally in the Earth  Rocks can contain one mineral (limestone) or more (granite)  Minerals are classified by their composition

Identification  Properties  Colour  Lustre- how they look in the light  Streak- colour of powder left behind when rubbed on a hard surface  Hardness- soft like chalk or hard like diamonds

How rocks form  Igneous rocks- form from hot, molten rock called magma (lava)  Sedimentary- small pieces of rock or shells settle or sink into rocks below them, these pile up and are compressed  Metamorphic- rocks that have been changed by heat and/ or pressure  Gneiss- same composition as granite but is metamorphic

Activity  Use key to identify rocks