Antique Fine Silver Overlay Glass Pitcher

This was either a wedding gift to my grandmother (1920) or my great grandmother.  It is 6" tall, opening 3 1/2", 15" around.  My grandmother called it a water pitcher.  Approx. 1 lb. 11 oz.  Beautiful design includes smooth and "hammered" silver overlay with colored enamel? painted on the glass (Looks a little like stained glass windows).  Mark at bottom of silver says "FINE.999SILVER"  Underneath that "5 5 A" .  On bottom of glass is etched "23-2"  Silver and glass in excellent condition; colored enamel? is faded in some places.  Have not found another example of this anywhere.  Would love to get any information possible.

Owned by my great grandmother, Katherine van Nest (b1870), wife of artist William Merritt Post OR their daughter (my grandmother), Katharine van Nest Post Gardner (b1906).