Art glass is manufactured specifically for use in artwork and comes in a huge variety of colors and finishes. Recycled glass is just not suitable for some art applications, including most of my custom/commission work, so I bring on the big guns: art glass.
This glass is tremendously malleable, easy to cut, easy to work with and achieves a variety of finishes. Some examples are below. I love it for its ability to show a third color where two colors touch.