English: Cannel coal from the Pennsylvanian of Ohio, USA. (bedding plane view)

The Linton Lagerstätte is a famous fossil deposit at the Diamond Coal Mine in far-eastern Ohio. It occurs in channel-filling, fissile cannel coal in the lower Upper Freeport Coal. The Upper Freeport is about 9 feet thick at this locality - bituminous coal in the Upper Freeport interval was the target for mining. The fissile cannel coal at the base of the Upper Freeport was waste rock and discarded in a large pile. Fossils include plants (palynomorph microfossils), invertebrates (principally conchostracans), and vertebrates (fish, amphibians, reptiles).

Cannel coals are odd varieties of coal. They don’t have the look & feel of ordinary coals such as lignite, bituminous coal, and anthracite. Cannel coals are lightweight, as all coals are, but are surprisingly tight and solid - they hold up to natural weathering pretty well, considering they’re coals. They are not sooty to the touch, and have conchoidal fracture (smooth & curved fracture surfaces). Cannel coals usually lack the well-developed horizontal bedding & laminations seen in lignites and bituminous coals.

Not surprisingly, the differences in physical characterstics between cannel coal and other ranks of coal are due to the organic matter content. Cannel coals are composed principally of fossil spores (sporinite phytoclasts). Garden-variety coals are composed principally of a mix of altered fragmented plant debris that was originally woody tissue, leaves, bark, fungi, and spores. Cannel coals are generally interpreted to have formed in pond, lagoon, or channel facies within a larger coal swamp setting.

Stratigraphy: lower part of the Upper Freeport Coal (= Number 7 Coal), Allegheny Group, Middle Pennsylvanian

Locality: Diamond Coal Mine, Linton, far-eastern Jefferson County, far-eastern Ohio, USA