Metallic luster describes a mineral that reflects light in a way similar to a polished metal surface, like aluminum foil. This means the light is reflected diffusely, giving the mineral a shiny, opaque appearance.

Here are some examples of minerals with metallic luster:

* Galena: A lead sulfide with a silvery-grey metallic luster.

* Pyrite: Iron sulfide, commonly called "fool's gold," has a brassy-yellow metallic luster.

* Chalcopyrite: A copper iron sulfide with a brassy-yellow metallic luster.

* Hematite: Iron oxide that can exhibit a metallic, steel-grey luster, especially when in a massive form.

Let me know if you'd like more information about minerals or their properties!