This is a rare unique French ex-voto in the form of a flaming heart, a devotional object typically used in Catholic folk tradition, especially in France and Southern Europe. The inscription says: "RECONNAISSANCE" (Gratitude) and "17 JUILLET 1916" (July 17, 1916) commemorating the lives lost in the Battle of the Somme. 5 1/2 inches long, 2 3/4 inches wide and 1 inch deep.
