File:Geology of the Richmond Basin 1899 Plate XL.jpg

English: Plate XL from The Geology of the Richmond Basin published by USGS, which has the following caption:
Coal bed of the Bingley slope in the Blackheath District. Looking north. Coal is exposed overlain unconformably (as shown in the upper left-hand corner) by the Lafayette pebble bed and yellow clays.

The text of the report refers to the figure as follows:

Famous in the early mining history of the Richmond coal field is the small area on the eastern margin lying mainly on the north of the line of the Southern Railway (see Pl. XXV). This area appears from the statement of old miners and from such information as can be gleaned at the present time from the materials about old pits to have contained two rather distinct troughs of coal, an eastern one known as the Blackheath Basin, and another one, known as the Cunliffe, lying between this and the main basin.

The Blackheath Basin, so far as is indicated by the outcrop of the coal, is of oval form, elongated in a north-and-south direction, and extends a short distance south of the tracks of the Southern Railway. At its northern end lies the old Bingley slope (see PI. XL), worked during the civil war by the government of the Confederate States. The coal seam here is thick, locally approaching 40 feet, but thinning southward, being at the railroad not more perhaps than 18 inches thick. Up to as late as 1897 individual miners took out coal from the upper pillars of the old workings. This coal found a market in Richmond. Beneath the upper thick seam of coal there is another bed, reported to be about 2 1/2 feet thick.