Clue 1 - Minerals - Station 5     How crystals form out of molten rock
Wednesday, May 09, 2012
8:39 AM
Station 5:  How minerals form and grow in an igneous rock
and 
Click to see how crystals form from molten rock
_____________________
Video of molten rock
Igneous rocks form when molten rock solidifies.  While the rock material is molten, in the form of lava or magma, few to no minerals exist and the atoms that will eventually settle into the patterns found in minerals are all jumbled together and unattached.
As molten rock cools, atoms begin to form attachments to particular atoms and arrange themselves into their solid pattern.  
Explore the interactive diagram that shows how igneous rocks form.
How do all igneous rocks form?
They form when loose grains of sediment stick together to form solid rock
They form when molten rock solidifies
They form when solid rock transforms into another type without melting
What is molten rock inside the Earth called?
Lava
Magma
What is molten rock that has escaped to the Earth's surface called?
Lava
Magma
How crystals form out of molten rock.
Does molten rock contain crystals of minerals?
Contains crystals of minerals
Does not contain crystals of minerals
Do mineral crystals grow from the center out OR the outside in?
Hint:  Use the resource that shows how minerals form in molten rock.
Grow from center outward
Grow from outside inward
As time passes while molten rock cools, do individual crystals grow larger or smaller?
Grow
Shrink
Crystal size as a clue to where molten rock cooled - inside the Earth or at its surface
In which place will molten rock cool more slowly?
Magma chamber underground
Lava flow at Earth's surface
Where do igneous rocks with larger crystals form?
Earth scientists consider any mineral crystals that can be seen with naked eye to be large. The more slowly molten rocks cool, the more time minerals have to grow to larger sizes.
Magma chamber underground
Lava flow at Earth's surface
The age of an igneous rock.
What does a geologist mean when they say that an igneous rock formed 30 million years ago?