Large Rectangle Art Noveau Sash Pin

This is a beautiful and unique piece of antique jewelry, Very Large Rectangel Art Noveau Sash Pin, Circa 1900 - 1920, measures 4-1/4" by 2 ", do not know what type of metal but looks like brass. This item has a 1" pink faceted stone that is in a bezel setting. the pin has a C-catch ,this is original to this period. It has never been clean ,I have had it in my personal collection for over 20 years. This item came from a local estate.