Coal fly ash procured from Guru Gobind Singh Super Thermal Power Plant, Ropar, Punjab, India, was analyzed for its mineralogical content and thermal stability by x-ray diffraction (XRD), thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), and physicochemical properties. XRD studies showed that major crystalline phases observed were quartz (SiO2) and aluminum silicon oxide (Al4.52Si1.(48)) with macro- and microelement (N, P, K, Mg, Zn, S, and Fe). Fly ash showed thermal stability up to 500 degrees C and reduction in weight was up to 200 degrees C, primarily due to loss of water and decarboxylation as revealed by TGA plots. FTIR of fly ash showed that the most prominent peaks in the spectra corresponded to Si-O and Al-O stretch vibrations. Coarse-grain accumulation of fly ash indicated the presence of 70% of fine-grained particles of 0.075mm. Coal fly ash was alkaline in nature (pH 7.85 +/- 0.03) with an electrical conductivity of 0.14 +/- 0.02 mu S m(-1), water holding capacity of 62%, low bulk density of 0.99g cm(-3), and a surface area of 0.96m(2) g(-1). With properties similar to that of soil coal, fly ash represents a suitable material for use in specific quantities as a soil amending agent in agriculture.