Xanadu portvinsglasHeight 16. 5 cm. Xanadu was drawn by Arje Griegst for Holmegaard. The glass matches the shell setting that Arje Griegst designed for Royal Copenhagen. The glass is made using a 5 part process, which has made it an extremely expensive glass to produce. The glass has an optical twist as the only decoration, this is achieved by blowing the glass into shape and then attaching the stem and twisting the optic inwards into the glass, and finally blasting the