In crystallography, the triclinic (or anorthic) crystal system is one of the 7 crystal systems. A crystal system is described by three basis vectors. In the triclinic system, the crystal is described by vectors of unequal length, as in the orthorhombic system. In addition, the angles between these vectors must all be different and may not include 90°.
The triclinic lattice is the least symmetric of the 14 threedimensional Bravais lattices. It has (itself) the minimum symmetry all lattices have: points of inversion at each lattice point and at 7 more points for each lattice point: at the midpoints of the edges and the faces, and at the center points. It is the only lattice type that itself has no mirror planes.
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Calculus 3: Tensors (8 of 45) Tensors for Crystal Structures: Triclinic

Crystal systems And Bravais Lattices  The Solid State (Part 4)

Crystal System  Bravais Lattice  Short Animated Video Classification of Crystal Structures
Transcription
Crystal classes
The triclinic crystal system class names, examples, Schönflies notation, HermannMauguin notation, point groups, International Tables for Crystallography space group number,^{[1]} orbifold, type, and space groups are listed in the table below. There are a total of 2 space groups.
#  Point group  Type  Example  Space group  

Name^{[2]}  Schönflies  Intl  orbifold  Coxeter  
1  Pedial  C_{1}  1  11  [ ]^{+}  enantiomorphic polar  Tantite  P1  
2  Pinacoidal  C_{i} (S_{2})  1  1×  [2^{+},2^{+}]  centrosymmetric  Wollastonite  P1 
With each only one space group is associated. Pinacoidal is also known as triclinic normal. Pedial is also triclinic hemihedral.
Mineral examples include plagioclase, microcline, rhodonite, turquoise, wollastonite and amblygonite, all in triclinic normal (1).
See also
References
 ^ Prince, E., ed. (2006). International Tables for Crystallography. International Union of Crystallography. doi:10.1107/97809553602060000001. ISBN 9781402049699.
 ^ "The 32 crystal classes". Retrieved 20180619.
 Hurlbut, Cornelius S.; Klein, Cornelis, 1985, Manual of Mineralogy, 20th ed., pp. 64 – 65, ISBN 0471805807