Vitreous from Latin 'Vitrum'

Vitreous Stones Reflect Light
Vitreous is the most common type of lustre seen in rocks minerals and particularly gemstones. Lustre is the term used to describe the way light interacts with the surface of a stone.
Vitreous comes from Latin 'vitrum' meaning 'glass'. Stones with a vitreous lustre reflect light in a similar way to glass.
The word implies the appearance or physical properties are 'glass-like'.
Article Photo
Our photo is a herkimer diamond from Herkimer County New York. The image is clickable and redirects to the original non-compressed photo. Courtesy of Stan Celestian.