Robert De Mario founded the company in New York City in 1945 after working for Miriam Haskell. De Mario jewelry is characterized by beautiful designs, excellent craftsmanship which often incorporates hand-sewn brass strung threads using faceted Austrian beads, rhinestones and pearls arranged in an array of harmonious colors, fashions and styles. The jewelry is relatively rare and high prices are received in the collectible market. Mark: "De Mario with and without a copyright symbol", "Hagler for De Mario" and "Hagler/De Mario". De Mario retired and closed his shop in 1965.