6
hematite rich and was exposed to high temperatures with a
high glass content.
Coal 108 is a highly altered sedimentary rock that was
exposed to very high temperatures with a melted/fused
nature (Figure 20) mullite and cristobalite, both high tem-
perature silicate minerals, are present as a possible result
of pyro metamorphization from the high temperatures this
sample was exposed to (Figure 21, Figure 22).
Coal 140 is a high temperature clinker that has a low
iron oxide percentage. It shows high glass content and
fusing of the minerals (Figure 23). Feldspars are present
through the sample with a high amphibole concentration,
possibly cummingtonite (Figure 24, Figure 25). Material
for this sample is a potassium rich protolith from the min-
erals seen in the sample.
Figure 18. Coal 107 thin section polarized light scan
Figure 19. Coal 107 Plane Polarized Light microscope
image. The different interbedded layers are distinctive by the
differences in color, grain size, and grain shape.
Figure 20. Coal 108 thin section polarized light scan.
Figure 21. Coal 108 reflected light. Mullite crystal in the
matrix
Figure 22. Coal 108 reflected cross polarized light. Mullite
crystal in matrix