Lustrous is defined as metals that have a shiny appearance. The shiny appearance of the metals is called metallic lustre.
Examples of lustrous non-metal
Metals have the quality of reflecting light from their surface and can be polished e.g., gold, silver and copper. Lead is an example of a metal that is non-lustrous. Non-metals do not have lustre. They do not reflect light from their surface. Non-metals have a dull appearance. Diamond and iodine are two exceptions and are lustrous non-metal.