Antique Christmas Tree Topper Ornament Wired Blown Mercury Glass 12.75 1920s

This is a wonderful blown mercury glass Christmas tree topper ornament, probably of German or Czech origin. The piece measures a 12 3/4 in height and hand decorated with wire overlay, tinsel curlicues at the side and tinsel hanging from the top. It is finished in a beautiful satin metallic blue colour. I believe that it dates to the 1920s, possibly earlier. It is in very good condition except for a bit of soiling to the interior opening and a couple of loose wires, and comes in its older storage box.
This is a very pretty display piece - exceptional addition to a vintage Christmas tree!