This tea bowl and saucer are made from rubinglas, also known as ‘Ruby Gold’ or cranberry glass. Although red is often seen in stained glass windows from the Middle Ages, a red glass suitable for the manufacture of drinking vessels was only perfected in the late 17th century by the German alchemist Johann Kunckel (1630-1703). While in charge of a glass workshop near Potsdam from 1678 to 1703, Kunckel conducted many glass experiments which he published in his treatise Ars Vitraria Experimentalis, in 1769. Unwilling to share his secret, Kunckel only briefly mentions his discovery of a brilliant ruby-coloured glass, achieved by adding a gold solution to a standard batch of molten glass. Rubinglas quickly became a prized material, not only due to the gold used to make it, but also due to the belief that gold was empowered with magical properties which protected against poison. Various workshops across Germany began to specialise in the production of hand-blown or molded rubinglas wares, especially in Dresden, Bohemia, Munich and Freising. Although this tea bowl and saucer are of relatively plain form, another example in the Chitra Collection features elaborate incised ornament and gold mounts often used to decorate German rubinglas wares (Chitra Collection no.521).