Vintage Czechoslovakian Brass Filigree Brooch with Peking Glass Cabochon

This is a vintage Czechoslovakian costume jewelry brooch, likely dating from the 1920s to the 1940s. The piece features an oval, horizontal format measuring approximately 1.75 inches in width. At the center is a large, domed, elongated oval cabochon of mottled yellow 'Peking glass' or 'slag glass,' designed to mimic the appearance of natural semi-precious stones. This central element is flanked by four smaller, petal-shaped glass inserts in a matching cream/yellow hue, which are set into decorative fleur-de-lis style hardware. The base material is a stamped brass with a dark, aged bronze-tone patina. The metalwork is characterized by intricate openwork filigree featuring scrolled and floral motifs typical of Czech production from the Interwar period. The craftsmanship exhibits the mass-produced yet highly detailed aesthetic of the Jablonec region. Condition-wise, the metal shows significant darkening and surface oxidation consistent with age, though the glass cabochons appear intact without major fractures. The mounting shows some unevenness in the filigree edges, and while a maker's mark is not visible from the front, such pieces are frequently stamped 'CZECHOSLOVAKIA' on the reverse pin mechanism.