Graphite is neither a mixture nor a metallic element. It's a non-metallic element.

Here's why:

* Element: Graphite is made up of only one type of atom: carbon. This makes it an element, not a mixture.

* Non-metallic: Graphite lacks the properties of metals, like good electrical conductivity, ductility, and malleability. It's considered a non-metal.

While graphite is made of carbon, which is an element, it's not a metallic element.