Van Gogh Glass is a mystery that I enjoy using in my work. It is made in the US, of glue chip glass(which has the lovely feathery patterning amazingly caused by special glue as it dries on the glass), painted with metallic automobile-type paint and then with a black coating. It has a three dimensional effect, as if you are looking into the depths of the glass. All this information comes from snippets from sellers of the glass, but no one actually claims the title of the manufacturer of this glass. Definitely a mystery, but a beautiful one.
Another Favorite V: Vitrium Glass Tile