Samples near the stoichiometry Y1Ba4Cu2Oxwere prepared with and without the presence of carbonate. XRD and wet chemical analysis were performed to determine carboinate content. A compound with the the stoichiometry of Y1Ba4Cu2(CO3)O7±&dgr;was stabilized when the precursor BaCO3was used. The absence of carbonate yielded the Y1Ba4Cu3O8.5±&dgr;compound. Electrical measurements indicated no superconductivity properties in the 10–298 K temperature range for the 142 oxycarbonate and the 143.