Glass art at the Adriaan Volkerhuis in Rotterdam, designed by architect Maaskant. Artist unknown. Strangely, the art work is positioned at the backside of the building, hardly visible or noticeable to anyone. It is also the shadow side of the building. Imagine how beautiful it would be when sunlight would shine directly through the coloured glass into the interior of the building.
p.s. According to one friendly commenter this artwork is made by Joop van den Broek (1928-1979). He also made large glass artworks for the Hilton hotel in Rotterdam and the Tomado house in Dordrecht. Both buildings, as well as the one pictured here, were designed by Hugh Maaskant.