The 32 Crystallographic Point Groups

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Models of all 32 Crystal Classes (= crystallographic point groups) for teaching or practice, with spoiler-free, randomized file names. Print as pre-oriented. I used known faces of typical minerals (e.g. diamond and calcite) or small molecule compounds (e.g. tartaric acid and AgI) where possible. For a few groups I could not find documented examples and had to freestyle. There are 33 files, because one example exists in D- and L-configuration (I didn't bother to do that for all chiral symmetries - you can just mirror the models). The pdf is just a printable A4 game board to help with sorting. Add color changes for extra fun - but beware that it becomes nearly impossible for students to figure out ;-) Some notes because people have asked: - There is one example per point group, but for each there is an infinite number of possible shapes. - I'm not claiming that all these shapes occur in the form of real crystals (some obviously do because I took them from books or fotos). - The difficulty level when used as a practical exercise is rather hard. - A real crystal cannot violate the point group associated with its crystal structure. It can have a higher-symmetry point group in the same branch, though. - This set was specifically designed "only" as a point group symmetry exercise, and I am not aware if something similar already exists. I would otherwise have used an existing kit, because I am a lazy person. It is definitely not designed to learn anything about crystal morphology in mineralogy, and I do not advise trying that.