USGS OFR 03-346
Figure 5a. Picture of typical iron-bearing ground water emerging as a spring. The iron
is oxidized to ferric hydroxide upon encountering the oxic environment of the surface. A large
number of these springs and seeps on the flood plain provide the iron for bog iron deposits.
Figure 5b. Samples of "bog ore" from Nassawango Creek show vugs lined with goethite
around massive "ochre".
Figure 5c. Transmitted light photo-micrograph is about 0.5cm on the vertical axis. Black areas of goethite may include magnetite that has been identified by X-ray diffraction of powdered ore. Light areas may be vugs or stained quartz.[an error occurred while processing this directive]