Each of seven categories of crystals (cubic, tetragonal, orthorhombic, trigonal, hexagonal, monoclinic, and triclinic) classified according to the possible relations of the crystal axes.
- ‘All of the forms in the isometric crystal system completely enclose space, making them regular geometric solids.’
- ‘Each mineral is carefully assigned a ‘Dana’ number followed by the accepted name, chemical formula, crystal system, and space group.’
- ‘There are only fourteen distinct types of Bravais lattices, and these are associated with seven crystal systems.’
- ‘Fundamental text for each mineral includes such information as varieties and colors, crystal system and mineral group, composition, characteristic identifying features, size, and distribution.’
We take a look at several popular, though confusing, punctuation marks.