Such cups are traditionally used in Chinese wedding ceremonies where the bride and groom are required to toast each other to a cup of wine. Dragon and phoenix relief designs differ in style when compared to the vase and bowl featured on your page. I frankly know very little about the cups. I bought them about a year ago from an individual who brought them in from China. He said they were antiques.
Fakes tend to be perfect.
There are no date, dynasty or source markings on the exterior. I am Chinese. In ancient Chinese practice, a newly married couple when retiring to their bedroom in private, toast each other to a glass of wine thus symbolically sealing a harmonious union. Any cup will do. However, peculiar to weddings, all appliances and decorations used bear a dragon and phoenix as a pair symbolizing the union of man and woman.