For this experiment, I used manganese dioxide and a much finer aluminum powder than in my other thermites, at a ratio of 2.42:1 MnO2:Al by weight (40g total). I've done this reaction before (but forgot to photograph it), and using my normal aluminum it produced a reaction similar to the iron thermite. It was a little brighter and produced more sparks. With the finer powder, things went a little differently. The small flower pot erupted in a pillar of flame about 6 feet high, with the sound of a rocket engine and heat that was felt a good 15 feet away. This is a great demonstration of the importance of particle size in thermite and most other reactions. I plan on posting a direct comparison, complete with pictures, sometime in the future.
Full reaction: 4Al + 3MnO2 -> 2Al2O3 + 3Mn
The reaction produces pure manganese metal, but I couldn't recover much of it because it was blown out in the ensuing fireball. I'd say it was worth it. Click the pictures for larger versions.