10.1.2: Identifying Symmetry
- Page ID
- 18466
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Looking for symmetry in natural materials can be complicated. Although atomic arrangements may be symmetrical, many things control crystal growth, so crystal shapes may not reflect their internal order. Sometimes few or no crystal faces may form. Sometimes several different crystals become intergrown. Sometimes crystals contain structural imperfections. Some crystals have pseudosymmetry, which means they appear to have certain symmetry but, if you could look closer or make precise measurements, you would find that they do not. And, other crystals may be too small to see clearly. An experienced eye and an active imagination are often necessary to see the symmetry of natural mineral crystals.