...are encountered in an upright position, with their larger roots still intact. Scattered through the dark clays are vast quantities of nodules of iron...reaching many tons in weight, and known to the miners as "white ore," "hone ore" or "steel ore." In the upper portions of the formation which have been exposed...

...are encountered in an upright position, with their larger roots still intact. Scattered through the dark clays are vast quantities of nodules of iron...reaching many tons in weight, and known to the miners as "white ore," "hone ore" or "steel ore." In the upper portions of the formation %vhich have been...

...unconformably ancient depressions in the surface of the underlying Patuxent formation. Scattered through these clays are vast quantities of nodules of iron carbonate, at times reaching many tons in weight. In the upper portion the carbonates have weathered to limonite. These ores occur along the western...

...highly carbonaceous, lignltized trunks of trees being often encountered in an upright position with the larger roots still intact. Scattered through the tough,...miners under the name of "white ore." In the upper portions of the formation the carbonate ores have changed to hydrous oxides of iron, which the miners...