This is a pure copper cup & saucer set, stamped on the back with "TWINBIRD," a company founded in the 1950s in Tsubame-Sanjo, Niigata, Japan. The glass cup is supported by a copper holder, creating a beautiful harmony between the luster of the metal and the transparency of the glass. The holder can be removed from the cup. The reflections when light hits it, and the deepening patina of the copper with use, are also part of its charm. Its appearance is well-suited for leisurely times, such as enjoying tea or herbal tea. It's also visually appealing just by being placed, so it can be enjoyed as interior decor. Likely from the 70s to 90s, this set has an atmosphere not found in current products. Please assess the condition from the photos. There is some aging of the copper.