Milagro Heart Charm Affirmation Necklace. Milagro means miracle in Spanish. This heart charm is sterling silver and is a cast impression of a genuine milagro charm. The gemstones are genuine peridot. Peridot is not only the birthstone for those born in August, Peridot is considered to be the stone of compassion, good health, restful sleep and peace. The gemstones are faceted. The necklace has a wonderful counter weight of a small milagros charm at the back clasp.