Dexter Perkins
University of North Dakota
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This is an introduction to the basic symmetry elements.

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This exercise is designed for a mid/upper-level undergraduate geology course on the principles of mineralogy.

Skills and concepts that students must have mastered

Students should have knowledge of basic chemistry and of minerals equivalent to what they would learn in an introductory geology class.

How the activity is situated in the course

This activity is the 23rd of 36 mineralogy exercises and is used towards the end of the course.


Content/concepts goals for this activity

  • Be able to identify symmetry in atomic strutures, crystals or other objects.

Higher order thinking skills goals for this activity

  • Develop ability to recognize patterns and deal with abstract concepts.

Other skills goals for this activity

Description of the activity/assignment

This is an introduction to basic symmetry elements. Students make drawings that show good examples of rotation axes and mirror planes and inversion centers with and without a 2-fold axis. They describe real objects a mirror plane, an inversion center, and 2, 3, 4, and 6-fold axes in 3D. They think about symmetry in atomic structures and indicate which symmetry elements are present in ball and stick models of minerals. Then they count the different kinds of symmetry elements present in wooden blocks and real minerals.

Determining whether students have met the goals

More information about assessment tools and techniques.

Teaching materials and tips

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