I agree collapsible cup,
There are Civil War / Indian War / Spanish American War era folding cups , nickel and silver plated , pocketwatch style case , advertising cups , engraved cups ,etc. in every size, material, and style . Some date from as early as 1860's Civil War era up to 1890's Victorian era and some will date into the 1930's and 40's by which time they were going out of favor. These were used by officers and some enlisted men alike in the early years. They were later used by gamblers , pioneers and travelers around the world and they became quite ornate and fancy by the end of the 19th century . It was common to see cups like these in the vest pocket or purse of wealthy gentlemen and ladies in the late 1800's to the early 1900's . Early in the 1900's they began using these as methods of advertisements in the form of Give-a-Ways or Premiums .
Nova Treasure
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