Problem Set 4

   1. In  #2a of problem set 3 concerning atomic structures of minerals, determine which minerals are
       isomorphs and which belong to the same isomorphic group?

   2. Do the same minerals which are isomorphs always have to display solid solution?. Explain

   3. Use the following description kinds of polymorphism to classify the following polymorphs as 
       enantiotropic, monotropic, reconstructive, displacive, or a combination of these.
         a. when subjected to high temperature, the bonds in mineral A break and reassemble structural
             units to form mineral, B

         b. mineral A changes to mineral B and vice versa with temperature change and there is only a
             slight displacement of the atoms to form different bond angles

         c. mineral A changes to mineral B but not vice versa

    4.  State the full mineral name with the associated mineral variety word modifying it below;

        a. hornblende rich in manganese

        b. tourmaline rich in Fe+3

           c. augite rich in aluminum

    5.  Using the table in the internet notes associated with Geothermometry, what mole % FeS would 
         exist in the mineral if it formed at 800 degrees C?  What about at 400 degrees C? What color
         difference would this cause in the 2 minerals?

    6. State the name of each mineral class represented by the following anion composition?

         a. (MoO4)-2      b.  (PO4)-3         c. S-2      d.  (AsO4)-3         e. (NO3)-1 

    7. State the name of the end members of the plagioclase series.  Why is there a different amount of
        each end member present in the minerals of this series?

    8. What is the basis of division in the classification scheme of mineral for mineral classes, subclasses,
         groups, series, and varieties?       

     Match the right column with the right column

____1. mineral subclass a.  perthite
____2. isomorphic group b. sulfates
____3. mineral class c. Cr+3
____4. polymorphic group d. sorosilicate
____5. end member e. flint
____6. chromian f. Fe2SiO4
____7. microcrystalline quartz or silica g. graphite
____8. exsolution h. sphalerite
____9. opal i. C
___10. geothermometry j. anorthite
  k. mineraloid
  l.  rutile


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