Review Questions for Lecture 16:
Earth's Crust; Phyllosilicates, Non-Quad Inosilicates
1. Phyllosilicates are characterized by what linkage of the SiO4
tetrahedra?
Why does muscovite have Al_2 whereas biotite has Fe_3
in the Y site?
2. Differentiate among the phyllosilicates: true micas, brittle micas
and clay minerals.
3. Describe the T-O vs. T-O-T structures. How can we use the 'c' unit cell
dimension to
distinguish between these two structures?
4. Describe the three different serpentine polymorphs.
5. Why is the term "clay" a confusing term?
6. Describe 'clay' minerals?
7. If you were choosing between building your house on a substrate
of illite or montmorillonite, which would you choose and why?
What does the presence of illite tell you about the geologic environment?
montmorillonite?
8. What is a non-quad pyroxene?
non-quad amphiboles?
9. What are the geologic environments indicated by:
spodumene?
aegerinne?
jadeite?
10. What other minerals are associated with:
spodumene?
jadeite?
aegerinne?
11. What is a pyroxenoid?
12. What is a biopyribole?