Answer:
Luster
Step-by-step explanation:
The term luster refers to the way light interacts with the surface of a mineral, rock, or crystal. This word originated from the Latin lux, which means light.
There are countless variations of luster, which is why there are no strict boundaries between the different types of luster. Some types of luster are dull, glassy (in fact vitreous is another term for the glassy structure; vitrum = glass in Latin), metallic, earthy, greasy, silky, pearly, etc.