These are dendritic opal palm stones, also known as Merlinite or dendritic opal agate. They are not to be confused with the stone, Mystic Merlinite, another name for Indigo Gabbro.
Dendritic opal agate is a form of chalcedony known for its black, tree-like formations, creamy white coloring, ash-gray segments, and caramel-brown and beige manganese and iron oxides that often beautifully stain many pieces.
This stone is said to be aligned with the solar plexus and third eye chakras, the elements of thunder/lightning and earth, the fusion of light and dark, and the zodiac signs Pisces.
It is a stone that symbolizes past life memories, lessons reflected upon, yin and yang energy, feminine and masculine harmony, balance, emotional openness, intuition development, awakenings, fusion, grounding, personal reflection, possibilities and broad vision.