G119

Objectives

Week 4 Feldspars and Quartz

 

1)  What is the silica tetrahedron, what elements make it up and what is its net charge?

 

2)  What causes cleavage in a mineral?  What causes fracture in a mineral?

 

3)  Understand what is meant by a mineral having a fixed composition vs. a solid solution.  Give an   

          example of each.

 

4)  Define "chalcedony" and give examples of microcrystalline quartz.  How do they differ from

          crystalline quartz? 

 

5)  What two physical properties could you use to tell quartz from feldspar?

 

6)  What is the chemical composition of quartz?

 

7)  Know why feldspars have cleavage and quartz doesn’t

 

 

Week 5 Objectives

The rest of the silicate minerals

 

1)  Describe the two primary types of chemical bonds found in the silicate minerals and give their

          relative strength (weak or strong bonds).

 

2)  Recognize the different silicate  mineral structures in a diagram  and show the location of covalent and ionic  bonds in each.

 

3)  Be able to describe how each of the following mineral groups differ in structure:

                          a.  olivines (separate tetrahedra)            d.  sheet silicates (mica, talc) ) (sheets)

                          b.  pyroxenes (single chains)                 e.  framework silicates (quartz, feldspars)

                          c.  amphiboles (double chains)

 

4)  List seven main mineral groups (i.e., sulfides, sulfites etc). Which group is the most abundant?

 

 

5)  Be able to identify the underlined/bolded silicate minerals from activities four and five without the aid of a flowchart or book.