This study found that promoted precipitated iron catalysts, containing large quantities of Hematite, demonstrated adequate activity, selectivity, and attrition resistance operating under commercial Fischer-Tropsch synthesis conditions in a product demonstration slurry bed reactor run over an approximately 170-day period. While small quantities of Hematite (< 10 to about 30 wt %) in the fresh catalyst have been demonstrated to significantly reduce the BET surface area, give rise to catalysts with poor pore structure, and consequently negatively impact the synthesis behavior, it was found that catalytic effective pore volume (> 0.30 cm(3)/g) and pore size (60-80 ) can be induced if larger quantities of about 30-40 wt % Hematite are present in the fresh calcined unreduced catalyst. The catalyst demonstrated exceptional attrition resistance.