HOYA Crystal Glass HOYA (Hoya Crystal) This contains high-quality crystal glass products from the HOYA brand. Crystal glass has higher transparency and a higher refractive index than ordinary glass, giving it a sparkling characteristic. HOYA's glassware is also popular in the second-hand market, with tumblers and sets being traded. Likely new. I believe it was purchased at a department store such as Mitsukoshi, Daimaru, or Sogo, or received as a gift.