Some of the samples used in Mineralogy Lab are museum specimens.  Please do not destroy them.  You can do just about anything you want to the grungy ones, but be nice to the pretty specimens as they are irreplaceable.
Name______________________________

MINERALOGY LABORATORY
Properties of Minerals and Intro to Polarizing Microscopes

The mineralogy text cited in this lab is Mineralogy, by Dexter Perkins. 

1.  Box of Rocks

	There are three trays (W4, W17, and W28) that each consist of an unknown igneous rock and the minerals that make up that rock.  For each of the three trays, examine the rocks and minerals and identify the minerals present in the rock using the list of minerals below.  You may find Appendix B of your text useful.

tray #	mineral present	
1a

		
1b

		
1c

		

A list of possible minerals.

Pyrite		     Riebeckite    apatite
Plagioclase/albite   Nepheline	Flourite
calcite		     Tremolite      Microcline
quartz		     Sodalite
hornblende	     biotite
Magnetite	     Labradorite

2.  Identifying unknown minerals	

	In tray #2, there are 15 unknown minerals.  Using your text (and any other sources you wish) and the skills you developed in last week’s lab, test the physical properties of each mineral and try to identify each mineral.  Record your results in your lab notebook using a format similar to that of the attached table.  Also, in the space provided below write a few sentences explaining how you were able to identify each mineral.  That is, what properties enabled you to make a positive identification.

**You may find the Appendices in the back of your textbook and additional text helpful.

3.  Introduction to polarizing microscopes.
	Read the pages on microscopes (from Perkins 2002). Pg64-70,75-77
 Then, answer the following questions.

	1).  What is the purpose of using a microscope?

	2).  Identify the parts of the polarizing light microscope shown in the figure above.  Then, describe the function of each part in a sentence or two.

	

	

	3) What is visible light?

	4) When is the wavelength range (meters) of visible light?

	5) What is meant by plane-polarized (PP) light?

	6) What is meant by cross-polarized (XP) light?  How do you get XP light?

	7) What is pleochroism?

	8) What are interference colors?

	9) What must be used (instead of a polarized light microscope) to identify a mineral if it appears opaque when being viewed under the microscope?

	10) What is the difference between isotropic and anisotropic minerals?

	11) Anisotropic minerals are divided into _________________ and ____________ minerals. 

sample	mineral	chemical
formula	crystal
habit	cleavage
fracture	hardness
tenacity	heft	luster
color	streak	other