Antique Edwardian Silver Dutch Button Filigree Brooch by Hand-Made

Known as Zeeuwse knoop/Zeeland knoop, & traditionally used in the costume of the Zeeland Islands (SW Netherlands) this style of button jewelry has been in use since at least the 17th century. I have found many examples of the Zeeland knoppen (buttons) used in antique jewelry, but only one other example of this size. Most likely used to pin a sash or belt, it's made of metal balls circled w/varying types of fine wire filigree -note that some are spiraled, while others have a checkered pattern. The center is a curling 'S' shape of these buttons, encircled by an oblong set of 14 buttons -2 of these being extra large. This design is mounted on a slightly tarnished silver framework base, w/the most interesting pin bar lock I've ever seen: it features a separate x-shaped lock that lifts into place to keep the pin bar locked tight! While I'm not a jewelry expert and have not had this piece examined, I have done extensive research & feel confident in saying this is REAL silver -evidenc