Relisted with better photos, first listing pics did not show this gorgeous pin accurately. It's still much more beautiful in hand than my updated photos show but at least these are an improvement, lol
This spectacular brooch is made by Schreiner of New York. Unsigned but with obvious construction details the most prominent one being the back which has the 2 part linked connector. Because the brooch is so high ( 2") it has a double ring so the hook and eye is not present. Taller hooks are used to connect the 2 rings together.
Schreiner of New York made many, many unmarked brooches. Some of these are quite easy to identify once you’ve handled marked pieces because the same settings were used with different stone and color combinations. Other pieces are quite unique, but still have notable attributes that point to Schreiner.
Some stones, like their large keystones found in highly coveted “ruffle” brooches were commissioned exclusively for Schreiner. Other stones used in their designs were made in very limited quantities, so they are not commonly seen. A number of those types of stones required special settings to be made to hold them. Schreiner was a company that made the extremely high domed brooches which was no small feat. Special components were made to accommodate this unique feature