I found what I think is a bone head many years ago at Whispering Pines Camp in Franklinville, NY, which is in Cattaraugus County. It was sitting exposed at the edge of a small stream that runs through the camp, on a hill. I apologize for not having scale in the photos. The measurements are: 2.5 cm thick, 4.5 cm across at very top, 3.5 cm top to bottom as pictured.