Holmium - Ho
These are two pictures of the two sides of a single sample of 1.5 grams of holmium metal. The metal has a clearly visible crystalline structure, which is best shown by the bottom picture. At that side, the sample is tarnished quite a lot, and it looks dark. The other side is less tarnished, but it already is somewhat yellow and less shiny. The untarnished metal is silvery/grey.