This is a 1950s Renoir of California copper brush and palette brooch with artificially added dark patina for greater visual interest. It is signed Renoir on the back.
"Midcentury Copper Masters", Curtis “Kurt” Freiler and Jerry Fels, ran the company from 1946 to 1964. They saw themselves as heirs of the Arts and Crafts movement.
Dimensions: 2.5 x 3.75 x 0.25 inch