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Petrographical and palynological coal-quality investigations relating to variations in one of the best-known and well-researched coalfields in Africa, the Witbank coalfield, and one of the most commercially important seams within this coalfield, the No. 2 seam, are highlighted in this paper. The investigations were based on 14 channel samples covering a 40 x 20 km2 area in the Witbank coalfield. The results indicate that the coals in the No. 2 seam were formed at the stage of major change-over from Dwyka to Ecca floras as illustrated by the progressive dying-out of Dwyka pollens and spores and the introduction of Ecca floral elements. This also suggests a rapid amelioration of climate over the period of peat accumulation, following a period of continental glaciation. Furthermore, it is proposed that the in-seam horizons reflect fluctuating of cyclic environments (probably due to changing water level) and plant communities (due to changing growth environments). Saccate pollens appear to occur in association with vitrinite-rich microlithotypes, trilete spores with inertodetrite and carbominerite-rich microlithotypes, and plicates with inertite semifusite/inertodetrite microlithotypes. Acritarchs (nonspinose) are present in parts of the seam where inertodetrite is common and in association with unusual suites of trace and major elements (possibly indicating changing geochemical environments in high groundwater conditions). Petrographic results indicate that the coals are medium rank (hypobituminous) and show wide variations in maceral, mineral, and microlithotype compositions, both vertically and laterally. On the basis of microlithotype and mineral-group analyses, investigations were undertaken to establish vertical subdivisions (by the study of historical patterns) and possible lateral correlations of these subdivisions in the area under investigation. These methods were then compared with distribution of selected chemical and geochemical parameters. The evidence suggests that a common sequence of major events (and some minor events) occurred during the accumulation of the No. 2 seam, as manifested by petrographic and palynological facies. Three major periods or zones are recognized. These tepresent periods of relatively stability (quiescence) separated by major in-seam disruptive events, namely, flood deposits bearing high proportions of detrital organic material or minor clastic sedimentation. These zones are subdivided into several subzones representing periods of reworking, local flooding or rise in ground water levels, and/or changing geochemical environments. These events can be recognized throughout the area under investigation, but the manifestation of these events varies from area to area, depending upon topographic situation, proximity to river channels, valley flanks or palaeoshorelines, degree of subsidence and compaction, geochemical environment, and length of time under a specific set of conditions. Thus, channels in close proximity to one another, or in similar positions relative to valley flanks or axes, appear to be remarkably similar to one another. Direct correlation of stratigraphic zones and sub-zones from sample site of sample site was therefore possible, although the methods to achieve this are complex and require the support of several supplementary/complementary interpretative techniques. Coal-quality variations and distribution within the original seam are therefore explicable in terms of the detailed factors listed above.