Which one of the following crystal forms DOES NOT belong to the di-tetragonal pyramidal class?
Show Hint
- c-Pedion
- Prism of 1st order
- Di-tetragonal prism
- Tetragonal dipyramid
The Correct Option is C
Solution and Explanation
The di-tetragonal pyramidal class belongs to the tetragonal system (point group 4mm) and includes crystal forms such as tetragonal dipyramids and prisms.
Step 2: Comparing the options.
(A) c-Pedion: Single face, characteristic of tetragonal scalenohedral or holohedral class, not di-tetragonal pyramidal.
(B) Prism of 1st order: Present in di-tetragonal pyramidal class.
(C) Di-tetragonal prism: Characteristic form of this class.
(D) Tetragonal dipyramid: Also belongs to this class.
Step 3: Conclusion.
Thus, c-Pedion does not belong to the di-tetragonal pyramidal class.
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