These earrings are silver plated. 
Black Tourmaline Healing Properties:
Tourmaline is believed to promote inspiration and happiness, reduce fear, and build self-confidence among its users. It's also used to balance yin-yang energies, as it's considered a physical bridge to the spiritual. Tourmaline comes in a variety of colors, the most common being black. Black tourmaline is one of the most coveted stones for protection and cleansing. It’s commonly used in rituals, grids, meditations, shrines and a variety of applications across continents, cultures and practices. Its ability to soak up, repel and banish negative energy is second to none in the healing crystal space. As it’s associated with the root chakra, black tourmaline is key in providing balance, security and grounding in your life.