Glass Covered Stones Are "Diagnostic"

Stones such as these, coated with glass, partly or fully, are "diagnostic" for the presence of a prehistoric pit iron furnace. Stones such as these Explorer Bill has found and collected ever since 1963. This collection came from "the Garrett Site," a spot along the North Fork of Paint Creek on the outskirts of Chillicothe, Ohio. Prehistoric furnace workers used stones to hold up the ore and charcoal that filled the upper part of the furnace bowl. The furnace bowls were dug into mounds, hillsides and creek banks. As the furnace smelts the iron ore, it melts silicon out of the ore. As the liquid glass then flows down into the furnace bottom it coated the hearth stones below with glass. After a furnace "burn" the bowl was cleaned out and reloaded with ore and charcoal to make more wrought iron.