C.K.K.K.+5.2

toc =Section 2 (5-2) Igneous Rocks=

Vocabulary
extrusive rock- is a form of igneous rock that is formed when lava erupts onto the earth's surface instructive rock- is a form is igneous rock that is formed when magma underground hardens beneath earth's surface porphyritic texture- is a rock with bigger crystals spread out on the background of a crystal smaller then it

**How igneous rocks form**

 * igneous rocks form when
 * hot molten/liquid lava/magma
 * cools and hardens

**Classifying igneous rocks**

 * igneous rocks are classified by their
 * origin
 * texture
 * and composition