Notices

Geometry of crystals

www.polymorf.net/knowhere1.htm

Lesson on the geometry and symmetry of elements and minerals using Polymorf, a new math and science manipulative. The topological approach is used to characterize the structure of crystals in terms of linked polyhedra. Elements and minerals are classified according to their atomic packing and the percent occupation of interstitial voids. Numerous models built with Polymorf demonstrate the lattice structure, polyhedral framework, and crystal habit.

Rick Engel, morfun@polymorf.net