Hafnium e-beam remelted Intermediate 02/13/2014 Europium sample Intermediate 02/13/2014 Europium Beginner 02/13/2014 Earth's Crust and Atmosphere Cross-Section Intermediate 02/13/2014 Diamonds Intermediate 02/13/2014 Crystalline Beryllium fragment Beginner 02/13/2014 Copper etched disc Intermediate 02/13/2014 Cobalt Beginner 02/13/2014 Cerium fragment Intermediate 02/13/2014 Cassiterite Beginner 02/13/2014