In 1709, the Signoria in Venice gifted filigrana glasses to the Danish king, Frederick IV for his castle at Rosenborg. Now referred to as Rosenborg-type glasses, these were technically different from earlier Venetian filigrana glasses made with two layers, or more specifically: a layer of canes on an inner layer of cristallo. With the exception of very large examples, the Rosenborg-type filigrana glasses, are made of a single layer of glass canes using a technique called filigrana a retortoli. The Rosenberg-type glasses also differ from the earlier glasses in that the bowl and the foot were blown and shaped from two different bubbles. Earlier Venetian filigrana glasses were often constructed from one bubble for both the bowl and foot. This Filigrana a Retortoli Wineglass bears the characteristics associated with the glass gifted to the Danish king. Not only does the wineglass consist of a single layer of canes, the foot and bowl are also made from different bubbles. The bowl is made of 26 canes, while the foot is made of 30 canes. This wineglass can therefore be attributed to Venice and dated to about 1700, although we do not have a firm attribution to know if it was made at the same glasshouse that made the gift for Frederick IV.