The conditions necessary for a laboratory-scale separation of the premaceral constituents of peat (i.e., the precursor to coal) are investigated. The method used is an isopycnic density centrifugation (DGC) technique aimed at isolating pure premacerals. This method, which is based on known density differences of various macerals, has been used successfully in coal separations but never with peats. The technique involved grinding the peats in a planetary ball mill to an approximate 10 mu m average particle size and conducting dispersion tests using NaCl, Ca(NO3)(2), CsCl, and TEE as solvents coupled with numerous surfactants. The density gradient centrifugation technique was run with both an aqueous and organic gradient using plain milled peat, demineralized peat, and demineralized methylated peat. The best separations were achieved in a single run if the peat was demineralized and dispersed with a wetting agent in an organic gradient. Analytical-scale separations were used to choose the most responsive peat to be used in a preparative-scale separation. A low and high density weight fraction, analyzed by flash pyrolysis, revealed distinctly different chromatograms, indicating that the pear had reached a reasonable degree of separation. Four peats of differing constitution are reviewed.