Form from
Magma (molten rock) or lava
How does magma form
Solid rock in crust / upper mantle partially melts
Why does magma rise
Magma is less dense. Cools as it rises due to geothermal gradient
Volcanic rocks are
Mafic and extrusive
Hypabyssal rocks are
Intermediate and intrusive
Plutonic rocks are
Felsic and intrusive
Aphantic
Indistinguishable crystal
Vesicular
Bubbly cavities
Pyroclastic
Other minerals inside
Porphyritic and phaneritic
Viable crystals
Pegmatitic
Coarse grain, large interlocking crystals