This is a Red Enamel Leaf Gold Tone Pin Brooch reproduced by the MMA - Metropolitan Museum of Art
The brooch is about 1 1/2" wide.
The description in the MMA pamphlet for this pin reads:
"A design for an engraved Niello ornament by Jean Tourin, who was active in France around 1618 to 1640 provided the source for this decorative leaf pin. The museum's reproduction is hard enamel on copper with 24kt. gold electroplate."
Please see picture that describes the significance of Niello art.