Up in the foothills of Nevada city , there are lots of Maidu artifacts like grinding stones. In a dried up pond I found a 2.5" perfectly oval stone with lots of tiny divets that make it look chipped away. I would think its an arrow head but there are no points, its tapered perfectly and is oval. It gets thinner on the edged but not to the point of a sharp edge, you can easily squeeze it without pain. I'm wondering what it is? Possibly a stone they used to grind with their palms in grinding stones?