Boron - B
This is a sample of 10 grams of boron. The purity of this sample is 93% - 94%. Boron is very hard to obtain in a real pure state and this sample already is very pure for a boron sample. The sample nicely shows that boron is black with a certain lustre, although different than metallic lustre.
Below follows a detailed picture of part of this sample. The large piece is approximately 1 gram of boron, the smaller pieces together are another gram of boron.
A much purer sample of boron was obtained from an eBay seller, who sells surplus chemicals from laboratories. The picture below shows some chunks of 99.7% pure boron. This pure boron is a little more shiny than the boron, shown above, but otherwise, it looks very similar.