Curated OER
Silica Tetrahedron Model
Very simply, pairs of learners construct a model of the tetrahedral silica structure using raisins and toothpicks. They dip it into a soapy solution and then blow a bubble "atom" into its center. The lesson plan gives instructions that...
Massachusetts Institute of Technology
Mit: Open Course Ware: Structure of Earth Materials
A college course featuring mineral image galleries, labs, and instructor's notes on the topics of crystalline structure, crystal chemistry, and bonding in rock-forming minerals.
Wikimedia
Wikipedia: Topaz
This encyclopedia article from Wikipedia provides a general overview of the gemstone topaz. Liinks are provided for additional information on related subjects.