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BELL SYSTEM TECHNICAL JOURNAL 



*3 Sphenoidal 



4 Domatic 



5 Prismatic 



Monoclinic system 



*6 Bisphenoidal] 



*7 Pyramidal [ Orthorhombic system 

 8 Bipyramidal J 



*9 Bisphenoidal 

 *10 Pyramidal 

 *11 Scalenohedral 

 *12 Trapezohedral 



13 Bipyramidal 

 *14 Ditetragonal Pyramidal 



15 Ditetragonal Bipyramidal 



*16 Pyramidal 



17 Rhombohedral 

 *18 Trapezohedral 

 *19 Bipyramidal 

 *20 Ditrigonal pyramidal 



21 Ditrigonal Scalenohedral 

 *22 Ditrigonal Bipyramidal 



*23 Pyramidal 

 *24 Trapezohedral 



25 Bipyramidal 

 *26 Dihexagonal Pyramidal | 



27 Dihexagonal Bipyramidal] 



Tetragonal system 



Rhombohedral system 



Hexagonal system 



*28 Tetrahed ral-Pentagonal-Dodecahedral 



29 Pentagonal Icositetrahedral 



30 Dj-akis-Dodecahedral 

 *31 Hexakis-tetrahedral 



32 Hexakis Octahedral 



Cubic system 



In addition to the above classification, the following list of minerals is 

 annotated with the following symbols: 



A = active by test 



I = inactive by test 

 R = unavailable or rare 



M = mineral occurs only massive, amorphous or 

 in other unsuitable form 



S = crystal always very small 

 H = mineral is always non-homogeneous 

 U = unstable 

 C = electrically conducting 



? = class not absolutely certain 



