Problem Set 1

        Use the atomic chart and common valences treated in the Mineral Chemistry calculation
         section to aid solving these problems--Use the textbook and look up the name of the
         mineral in the appropriate problems

---practice makes perfect--practice more with data for other minerals in chapters 15-17 and 19, inclusive
1.  Calculate the weight % of each element in the mineral having the formula, Cu3AsS4. 

2.  Calculate the formula for the mineral which has the following weight % com-
      position                Ag+1 = 65.4%    S-2 =19.4%  As+3 =15.2%
     
3.  Calculate the weight % of each element oxide in the mineral having the formula, PbMoO4
                                                                  Mo = +6 valence

4.  Calculate the weight % of each element oxide in the mineral with the formula,
     Co3(AsO4)2.8H2O                As = +5

5.  Calculate the formula (all water as yH2O) for a mineral which has the following element oxide
      weight % composition         Na2O = 22.7%      B2O3 = 51.0%    H2O = 26.3%     
     Also, determine all possible mineral formulas with different water compositions
     If the (OH)x : yH2O or x : y =2 : 3 or 4 : 6, what would be the correct formula for the mineral???

6.  Given the following mineral formulas, determine the valence of the element listed as "X"  in
      each formula
                   a.   NaXB5O6(OH)6.5H2O
                   b.   ZnX2O4           
                   c.   Pb5(XO4)3Cl
                   d.   Zn4(X2O7)(OH)2.H2O
                   e.   Ca2Al3X(SiO4)(Si2O7)(OH)

7.  Given the following unit cell dimensions in Å (Angstroms), calculate the axial ratios for each
        of the 2 minerals a, and b
                          a. a = 5.0                        b.   a = 7.0
                              b = 8.1                              b = 4.3
                              c = 14.3                            c = 23.1

8.  Given the following parameters, calculate the Miller Indices
                           a. 2a: b: 3c                   d.   a: a: 3c
                           b. a: infinityb: infinityc    e.  4a: 3a: 9a
                           c. 2a: b: 5c                    f.    3/2a: 4/5b: 6/11c

9.  Calculate the specific gravity of a mineral with the following information given:
      composition: BeO = 19.8%  Al2O3 = 80.2%         Z = 4          
      axial dimensions of unit cell:   a = 5.47Å     b = 9.39Å    c = 4 .42Å

10. If a face of a form on an orthorhombic crystal intersects the a axis at 33.96Å, the b axis at
      44.6Å, and the c axis at 15.41Å (all measured from the axes intersection or vortex) calculate
                 a.   the parameters of the face    
                 b.   the Miller Indices   "                GIVEN:   the unit cell dimensions:
                                                                                   a = 11.32Å    b = 22.30Å    c = 30.82Å

11. Determine the number of faces comprising each form below:
                 a.   Hexagonal scalenohedron                      g.   Pyritohedron
                 b.   Ditetragonal pyramid                             h.   Dihexagonal pyramid 
                 c.   Rhombohedron                                      i.   Ditrigonal dipyramid 
                 d.   Tetrahexahedron                                    j.   Rhombic dipyramid
                 e.   Trisoctahedron                                       k. Ditetragonal prism
                 f.    Dodecahedron                                       l.   Trigonal dipyramid 

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