Antique Pewter Wine Goblet 19th Century 500g 18 Cm 7 ⅛" Tall. I would not say that the goblet is completely straight on its stem full stop diameter across the base is 4.5 inches or 11.5 cm. Total diameter across the lip is 11.1 centimeters or four inches and 3/8 one way but it is a tiny bit squigged so the dimension the other way is four inches or 10 centimeters.