Iron pyrite, recovered from massive pyrite deposits or as a byproduct of the flotation of complex sulfide ores, is an important feedstock in many local areas. Its use has diminished substantially over the past decade owing to increased availability of sulfur recovered from petroleum refining or from the smelting of metal sulfide concentrates. Outside the United States, but within other market economy countries, the important frasch sulfur deposits are in Mexico and Iraq. Deposits amenable to exploitation by the frasch method are those that can be melted and extracted by injection of hot water and compressed air. Data concerning both frasch and pyritic sulfur properties are summarized herein. The report summarizes the results of work completed under contract and is presented as a project overview. The number and descriptions of the various technical reports prepared and submitted are outlined. Various property list changes implemented by contract modifications are noted. Methods of data acquisition and analyses are described and useful findings of the study are discussed. Difficulties and problems experienced during the project are highlighted.