This is a very rare piece of 17th century English lead glass in form of a footed bowl or compote. The bowl having nipt diamond gadrooning and a trailed band above it. When this sold at Bonham's London in 2010 they identified it as a wassail cup. I'm not sure how they determined that use. Here is their listing - https://www.bonhams.com/auction/17813/lot/39/an-early-wassail-cup-circa-1690/ Height 23.81 cm (9 3/8") Diameter at top 20.32 cm (8 inches). Minor open bubble on inside bottom of bowl. Possibly unique.