This lovely brooch is made from sturdy die-stamped brass with applied embellishments, and decorated with what appear to be four faux garnets. It is 3-1/8" across, and 2" high, with a thick pin stem (which is indicative of a sash pin, worn at the waist in Victorian and Edwardian times).
This is probably a later piece, produced perhaps in the early 1900's or 1910's. It appears to have a touch of Art Deco look in the angularity of its stamped design, so perhaps it is a transition design between Art Nouveau and Art Deco. Simple "C" clasp. Excellent condition.