In mining, concentrate is partially purified ore. It is produced by mixing ground ore with water and blowing air bubbles through the water. These carry mineral particles to the surface.

This is the final purely mechanical step in the process, and is the output of mining as such. As such, concentrate production is a measure of the output of a mine (or mines).

The concentrate is then smelted to produce pure metal. Smelting is a thermal (the molten metal separates from the solids and gases that result) and chemical process (thermal decomposition f metal compounds, oxidisation of carbon, etc.).