Dendrite & Herkimer Diamond Double Stone Adjustable RingDendritic Agate & Herkimer Diamond set in sterling silver. Please inquire directly in store or for availability of current ring shapes and colors or for a virtual shopping experience. Dendritic agate, also known as "tree agate," is a stone that symbolizes growth, stability, and connection to nature. Herkimer diamonds are associated with healing, increasing spiritual energy, and opening chakras. They are also known as the "stone of attunement."