The program in June will be Danville Porcellanite: Documenting an Ancient Coal-Burn in the Illinois Basin presented by Brad Koldehoff.
The presentation discusses the only known ancient coal-burn in the Illinois Basin. Sometime before the last Ice Age, coal beds near Danville, Illinois burned converting adjacent shale layers into a fused, porcelain-like material called “porcellanite” by geologists and archaeologists. This natural ceramic material fractures like flint and thus was used by ancient native groups as earlier as 9,000 years ago to make spear and arrow points. This material is rare in Illinois but is comparable to vast deposits of porcellanite and clinker exposed today across parts of Wyoming and Montana.
The presentation discusses the only known ancient coal-burn in the Illinois Basin. Sometime before the last Ice Age, coal beds near Danville, Illinois burned converting adjacent shale layers into a fused, porcelain-like material called “porcellanite” by geologists and archaeologists. This natural ceramic material fractures like flint and thus was used by ancient native groups as earlier as 9,000 years ago to make spear and arrow points. This material is rare in Illinois but is comparable to vast deposits of porcellanite and clinker exposed today across parts of Wyoming and Montana.
