nes 1980, 105). !
             In 1979, boron exports were estimated to have reached a record high level of 132,000 tons (Bureau of Mines 1980, 105). U.S. imports of boron ores and boric acid declined from the peak of 15,000 tons of boron content in 1978 to 11,000 tons in 1979 (Bureau of Mines 1980, 105). From a 1978 base of 128,000 short tons of contained boron, U.S. demand is forecast to grow at an average annual rate of 3.8% to 290,000 tons in 2000 (Bureau of Mines 1980, 105). Cumulative U. S. demand in this period, at 4.4 million tons, represents over one-fifth of estimated domestic reserves of 20 million tons (Bureau of Mines 1980, 105). World reserves of about 100 million tons of boron content are more than adequate to satisfy cumulative world demand to 2000 of 15.4 million tons (Bureau of Mines 1980, 105). The average rate of growth in world demand, from 460,000 tons in 1978 to 980,000 tons in 2000, is 3.5%.
             Borate minerals have been used in a wide range many centuries, dating from at least the 8th century when they were used primarily as a flux for assaying and refining gold and silver (Kistler et al 1994, 171). Their valuable properties and relative rarity soon stimulated international trade in borates. Marco Polo claimed to have transported Chinese borate minerals from Tibet to Europe, and his home of Venice was the center for borate imports and use throughout the Middle Ages (Kistler et al 1994, 171). In 1777 the mineral sassolite, naturally occurring boric acid, was discovered in the hot springs of Tuscany, Italy, which from 1827 to 1872 supplied most of the boric acid and borax for European markets (Kistler et al 1994, 171). In 1808, during a time of rapid advancement in chemical science, Jeseph Luis gay-Lussac and Louis Jacques Thenard of France and Sir Humphrey Davy of England discovered almost concurrently the element boron (Bureau of Mines 1980, 105). Another centu!
             ry passed, however, before boron was successfully...