A summary of phosphate-rock resources of the United States-an analysis of past estimates

The United States produced in 1980 about 54 million tons of phosphate rock, which was 40 percent of the world production. About 62 percent of this production was exported, 28 percent as phosphate rock and 34 percent is manufactured fertilizers and chemicals. The remainder was used domestically, largely (88 percent) for fertilizer and animal feed supplement to produce agricultural products (U.S. Bureau of Mines, 1981). A significant portion of these agricultural products was exported, so the phosphate rock that went into that portion was exported indirectly. Thus, most phosphate production is exported directly or indirectly and contributes to the U.S. balance of international payments. Although the marketable value of the phosphate rock produced in 1980 was only about $1.2 billion, the total value of the agricultural and chemical products depending on phosphate rock input is many times that. The continued ability of the U.S. phosphate industry to supply low-cost phosphate rock for export and domestic consumption is clearly of major importance to the Nation.