Question

What is lustre?

Answer 1

When you look at precious stones and minerals, you will notice some are shiny and some are not so shiny. That's because these substances reflect light in different ways. Some can look 'glassy,' and there are others that can be described as 'waxy.' There are some that do not really reflect light well, so they can be described as 'dull.' The way that these objects reflect light differently can be attributed to a property called 'luster.'

Lustre is a property that describes how light is reflected on the surface of a mineral. It is one of the properties mineralogists look at when trying to determine the identity of a mineral.

Lustre or luster is the way light interacts with the surface of a crystal, rock, or mineral.
A gentle sheen or a soft glow.