Word: quartzes
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...Quartz crystals are harder to grow than the tenderest orchids. How nature does it is not exactly known, and nature does not produce enough big, perfect crystals to provide electrical manufacturers with the quartz slices they need to control radio frequencies...
Blending powdered quartz, magnesite and bauxite, the bureaumen added a crystallizing agent (fluorosilicate compound) and melted the ingredients in a platinum-lined crucible at nearly 2,500° F. As the furnace cooled, mica sheets grew from tiny "seed crystals" at the coneshaped bottom of the crucible. Because crucibles lined with carbon or ceramic failed to do the trick, the bureau scientists used expensive platinum, hope to reduce costs by melting down the metal and reusing it time & again...
...Francisco River is South America's fifth longest;* for more than 1 ,000 miles it winds northward from the quartz-bearing uplands of Minas Gerais through the arid, scrub-covered backlands of Brazil's northeastern bulge. Then, suddenly, it hurls itself 275 feet down a jagged granite precipice in the spectacular Paulo Afonso Falls...
...Bathysphere ($12,000). Fifty-seven and a half inches in diameter, weighing 7,000 pounds, it is more stoutly built (of 1¾ in. steel) for the tremendous pressures at lower depths-2,000 pounds per square inch at 4,500 feet. It also has a new three-inch quartz window, slanted toward the bottom; the Bathysphere had side windows only. It carries a six-hour supply of oxygen in cylinders, fans to keep the air circulating, and trays of soda lime to absorb the carbon dioxide given off by breathing...
...needed Brazil as a strategic base and as a continuing source of essential minerals (manganese, quartz, mica). Today, Brazil is the cornerstone of the U.S. policy of hemispheric defense. Brazil, which benefited greatly from U.S. wartime expenditures, looks to the U.S. in peacetime for the aid that private and public capital can give to the building of the country. Brazilians want to tap U.S. technical skill for the development of the natural resources that are spread in abundance over the world's fourth largest nation. In area, only the U.S.S.R., China and Canada are larger than Brazil...