Igneous Rock Lab ( 32 points)
Name:______________________
Due Date:_________________
Directions: Use the identification key to identify the igneous rocks below. There may be repeats of
some rocks.
Pre-lab Questions: (3 points)
Coarse Grained= Cooled _____________________
Fine Grained= Cooled ___________________
Felsic= mostly made of _____________________ minerals
Mafic= mostly made of______________Minerals
Rock ID Chart (20 points)
Rock Sample #
Texture
(coarse/fine grain)
1
2
3
4
5
6
7
8
9
10
Color
(felsic/mafic)
Other
Observations
Rock Name
Questions: (Full sentences are not necessary, unless specified)
1. Do all igneous rocks contain crystals? Explain your answer with a full sentence. (2 points)
2. Why do some igneous rocks have bubble holes (vesicles)? (1 point)
3. What does crystal size and color tell you about the formation of an igneous rock?
(2 points)
4. Explain how the granite in St. Cloud was formed. Your answer should include the vocab terms
batholith, intrusive, coarse grained, and felsic. Explain your answer with 1-2 full sentences.
(5 points)