Bannerstones are artifacts usually found in the Eastern United States that are characterized by a centered hole in a symmetrically shaped carved or ground stone. The holes are typically ¼" to ¾" in diameter and extend through a raised portion centered in the stone. They usually are bored all the way through but some have been found with holes that extend only part of the way through. Many are made from banded slate or other colored hard stone. They often have a geometric "wing nut" or "butterfly" shape but are not limited to these. More than just functional artifacts, bannerstones are a form of art that appear in varying shapes, designs, and colors, symbolizing their ceremonial and spiritual importance.