Murano Glass Calcedonia Double Abstract. Calcedonia, developed in the mid-15th century, is one of the most ancient and rare types of Murano Glass. The alluring striations, achieved by adding silver nitrate, become wonderfully unpredictable creating works of unparalleled beauty. Signed by the Murano Glass Master Andrea Tagliapietra. Genuine Murano Glass made on the island of Murano Italy. Murano Glass Certificate of Authenticity included with each item. The extraordinary quality and elegant design of this hand blown sculpture, 16” Ht. 9.5" Width 6.5” round base, will add a sense of luxury to any home. As each item is individually handcrafted, no two pieces are exactly alike with slight variations in size and color.