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Oxygen contents of 21 Kentucky and 14 Penn State Data Bank (PSOC) coals have been determined by fast neutron activation analysis (FNAA). All analyses were done with freeze-dried coals. Oxygen contents of low temperature ashes and acid demineralized (AD) samples from the PSOC coals were also measured. FNAA oxygen analyses on AD samples yield organic oxygen contents directly, while total oxygen minus LTA oxygen by FNAA provides an independent organic oxygen value. A pyrolysis-coulometry method of oxygen determination was also applied to the AD and whole PSOC coals. All these methods yield results for organic oxygen which are generally in good agreement. Results obtained by ASTM and Given's oxygen-by-difference methods based on ultimate analyses agree in many, but not all cases. Several equations were developed to express the correlation between inorganic oxygen and silicon on a freeze-dried, whole coal (wc) basis. The best fits to experimental data were obtained with quadratic and log-log equations. The preliminary quadratric equation developed is: (Dinorg)/sub wc/ = 0.835 + 2.959(Si/sub wc/) - 0.0654(Si/sub wc/) exp 2 . This equation partially compensates for high contents of quartz and/or non-silica oxygen minerals (e.g. carbonates and sulfates) which deviate significantly from clay mineral O/Si stoichiometry. Only 3 out of the 35 coal samples analyzed deviated appreciably from the above relationship. The mineralogy of the samples is currently being studied and a detailed interpretation of the data will be presented later. 29 references, 4 figures, 12 tables. (ERA citation 09:027786)