Coal resources in southeastern Nigeria occur across contrasting geological settings and exhibit substantial variation in rank, petrographic composition, mineral matter, moisture, volatile matter, ash yield and energy potential. This study presents an integrated geological, mineralogical and energy assessment of Ihioma lignite in the Orlu area of Imo State and the better-established sub-bituminous coal resources of the Enugu area, southeastern Nigeria. The assessment combines published geological and stratigraphic evidence with reported proximate, ultimate and mineralogical data for Ihioma lignite and published petrographic and physicochemical information for Enugu coal. Ihioma occurs within the Tertiary sedimentary succession of the Anambra Basin and represents a lower-rank coal resource than the Lower Maastrichtian coal of the Mamu Formation. Published analysis of an Ihioma lignite sample reported moisture of 6.0%, ash of 4.0%, volatile matter of 38.5% and fixed carbon of 51.5%, together with reported carbon, hydrogen, nitrogen and oxygen concentrations of 64.6%, 4.0%, 1.064% and 2.0%, respectively. Hematite was identified as the principal mineral phase, with quartz and albite among the subordinate minerals. The reported low sulphur content is potentially advantageous for thermal utilization, although broader sampling is required before regional conclusions can be made. Enugu coal, by contrast, belongs predominantly to the sub-bituminous range of the Lower Maastrichtian Mamu Formation. Earlier rank studies identified a progressive decrease in rank from Enugu toward northern coalfields, with Enugu samples reaching sub-bituminous A rank. Published studies further indicate that the Mamu Formation accumulated in a paralic to deltaic depositional system characterised by repeated alternation of sandstone, siltstone, mudstone, carbonaceous shale and coal. The contrasting rank and mineralogical characteristics of Ihioma and Enugu demonstrate that southeastern Nigerian coal resources cannot be treated as a homogeneous fuel. Ihioma lignite may have potential for low- to medium-temperature thermal applications, briquetting, industrial heat and selected non-fuel uses, whereas the higher-rank Enugu coal presents a stronger case for conventional thermal and metallurgical evaluation. Nevertheless, commercial development should be preceded by systematic drilling, proximate and ultimate analyses, petrography, trace-element characterisation, calorific-value determination, ash-fusion testing, washability studies and environmental baseline assessment. The study concludes that the greatest opportunity for southeastern Nigerian coal lies in resource-specific beneficiation and diversified utilization rather than indiscriminate combustion.