Chocolates and cakes with various `inclusions' (filings)
can be used to provide an excellent analogy to textures in real rocks. Students
learn not to take the initial appearance of rocks for granted and learn to appreciate
the complexity of analysing rocks, underlining the value of sending a human
to study rocks on Mars over robotic missions.
The experiment will take approximately one hour to complete, but can be expanded or contracted, depending on the amount of time and resources available and the nature of the students. The lesson could be entirely based on pictures of rocks and edible samples if actual edible samples are impractical. The number of samples described and the length of any discussions may be extended or reduced by the teacher as appropriate. The discussion and/or the scope of the activity may be extended to include other rock types and their equivalent edible form. The choice is yours!
This experiment is an adaptation of the Hawai'i Space Grant Consortium's 'Edible Rocks' experiment. You can find out more about their experiment from their web pages.