Igneous Rocks

People throughout history have used igneous rock for tools and building materials.

• True

• False

BASALT is used for cobblestones and in landscaping.

• True

• False

EXTRUSIVE rock forms beneath Earth's surface.

• True

• False

Magma that is LOW in silica usually forms light-colored rocks, such as granite.

• True

• False

Igneous rocks are classified by their origin, texture, and mineral composition.

• True

• False

Extrusive rocks have larger grains than intrusive rocks.

• True

• False

Which terms best describe igneous rocks?

• Light and easily broken

• soft and smooth

• Hard and dense

• Soft and dense

How do coarse-grained igneous rockks form?

• From sedimentary ocks changed under pressure.

• from large rock particles cemented together.

• from rapidly cooling lava.

• from slowly cooling magma.

Which igneous rock is mixed with soil and used for starting vegetable seeds?

• Perlite

• Granite

• Obsidian

• Basalt

Which igneous rock is an extrusive rock?

• Porphyry

• Rhyolite

• Pegmative

• Granite