Shell on a dolphin, Ottavio Miseroni (stone cutter),  Prague, 1605-1610. Rock crystal, gold, enamel. 12.8 x 17.5 x 9.8 cm, base 6.6 x 5.2 cm. V 310. Green Vault © Staatliche Kunstsammlungen Dresden 2013

Exotic sea snail shells and clams served as an ideal model for the delicate shell of rock crystal. Gems in inventory of 1725 it is described as "A Cristallne shell, then drehet than a bang eights screw back, [...], on the ground the herb ivy is cut, the foot of a Cristallen Delphingen so the Kopff and cock after Forder turn unto part, [...]. " To make a cup of this artistic quality it required exceptional skills. What could be overcome only through complicated and tedious grinding work, gives the illusion that it would be, so with a light hand molded from wax. Vessels of this type were typical of the "soft" style, which determined the glyptic Ottavio Miseronis in the years 1600-1612. The Milan-based artist has worked since 1588 at the court of Emperor Rudolf II (r. 1575/76-1612) in Prague and produced especially vessels of jasper, agate, jade or heliotrope. In the area of vascular section, "arte Grossa," was his strength. He has not worked in nearly such a large scale as the Miseroni working in Milan rock crystal.Thus, the ranks obtained in the Green Vault, lightweight bowls as well as precious as rare work of mountain crystal cut in the impressive oeuvre of Ottavio. It may be that the shell of the three rock crystal vessels, the Christian II of stuff (reigned 1601-1611) demonstrated acquired by Ottavio Miseroni and paid in July 1610.