These models can be used in several ways by those who want to:

  1. make interesting shaped boxes
  2. learn about the symmetries of polyhedra
  3. learn to identify crystals and minerals based on their 3D symmetries.

You may want to print this first page on ordinary thickness paper and have it by you for reference when making the models.

There are 8 models, one for each of the 7 crystal classes and an extra one as a puzzle for you to find its symmetries and decide to which class it belongs.

There are some pages of explanation and exercises for those interested in symmetries, and one page for each model with some details and a plan for making the model. The models are stored in 2 formats:

The model names and the (RISCOS Drawfile names) in which they are stored are:
  1. Cubic, 'Cube'
    (sometimes called isometric)
  2. Tetragonal 'Tetrag'
  3. Orthorhombic 'Orthor'
  4. Trigonal 'Trigon'
  5. Hexagonal 'Hexag'
  6. Monoclinic 'Moncl'
  7. Triclinic 'Tricl'
  8. Calcite 'Calcit'
There are two sets of instructions, for making:

Instructions for Making boxes

Instructions for Making closed Models

This is simpler than making the boxes described above, but before starting you may want to look at the file 'Unitcells', which is an explanation of the different classes of crystal, based on the angles between the faces, the lengths of the sides and the number of rotational symmetries.

You may want to print out this file and the two in files Page4, Page5 which have suggested exercises for you to do with the models after they are completed.

Each of the model files has the plans for a model and a few details about its symmetries.

Exercises to try when you have made all the models

There are two files ('Page4', 'Page5') have 8 rows of shaded 3D views of the models shown from different view points. All the views in a row are of the same model. No model is repeated. Print out these pages, then use your set of models to help you decide decide which model is shown in each of the 8 rows, identify the view points, and draw the appropriate symmetry symbol where the symmetry axis goes into the model.

Rotational Symmetry Symbols

There are many symmetry symbols; these models only show a few of them, these are all filled shapes, usually black:
crystallographic symbols

Useful Books

1. "A guide to Understanding crystallography", Jennie R.Smith, 1991 A special publication of the Rochester Mineralogical Symposium, This book is intended for mineral collectors.
2. "Crystals and Crystal growing", Alan Holden and Phyllis Morrison, MIT Press edition 1992

ISBN 0 262-58050-0 pbk. This book is for adults; it is useful to teachers running crystal growing competitions in primary and junior schools, it has many details about crystals and their shapes

3. "Crystals " Gordon Cressey and Ian Mercer, 1999 published by the Natural History Museum, London
ISBN 0 565 09145 X. This is a full colour paperback booklet showing many beautiful crystals and describing where they are found and their uses in modern technology. It has a brief summary of crystal symmetries.

4. "International Tables for Crystallography, brief teaching Edition of Volume A Space-Group Symmetry". Editor Theo Hahn. Published for the International Union of Crystallography by Kluwer Academic 1993 ISBN 0-7923-2271-1
This has a full list of graphical elements for symmetry symbols; it tries to explain in detail a few of the 230 space group symbols found in the full edition. Only interesting to crystallographers

Page last updated 10 September 2003
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