This is a 4" x 2" x 2" glass sculpture by Pavel Molnar, a pioneer of the Studio Glass Movement. He was born in 1940. We bought this from him in his studio in Cesky Krumlov in the Czech Republic in 2007. We were told that the gray color was uncommon. It shifts to blue in some light and a little amber. There are also bubbles trapped in the glass. Very beautiful piece of glass. I won't be including the brochure with it, I have a couple more pieces of his glass here.