 When
molten rock (lava) cools and becomes
solid
 Intrusive: cools slowly
 Extrusive: cools quickly
 Contains
bubble-like holes
 Hard
Bubbly texture
 Formed above or below earth’s surface

 Granite
 Basalt
 Pumice
 When
heat and pressure cause older rocks to
change into new types
 Formed deep in the earth
 Fine
texture
 Has bands or streaks of minerals
 Usually made of quartz and calcite
 Marble
– comes from limestone
 Slate – comes from shale
 Quartzite – comes from sandstone
 When
rocks, plants, and loose material get
pressed into layers over time
 Involves weathering and erosion
 Has
layered features
 Very soft (easily scratched)
 Contains fossils
 Made of particles cemented (pressed)
together
 Limestone
– made from seashells
 Shale – made from mud
 Sandstone – made from sand