2. basalt contains mostly plagioclase feldspar, augite, and olivine

3. some rocks are made of only one mineral ex: limestone and marble contain mostly calcite

4. Igneous Rock

5. fine texture: small crystals (or even no crystals) examples: obsidian (volcanic glass) pumice (volcanic glass foam; it floats in water) scoria (sold as “lava rock”) basalt (most common rock on Earth) rhyolite (light colored) andesite (medium colored)

6. or… magma like lava, but below ground rock is called intrusive or plutonic underground igneous rock structures are called plutons

7. coarse texture crystals large enough to see with unaided eye examples: granite (most common rock on continents) gabbro (like coarse grained basalt) diorite (like coarse grained andesite) pegmatite (very large crystals)