Resumo de Book Of Facts - Reader's Digest

RICHES FROM THE EARTH-III

BRILLIANT DISPLAY

The French statesman Cardinal Jules Mazarin invented in about 1650 the shape known as a ?brilliant?- in which a diamond or other gem is cut in precisely angled facets. He had 12 large diamonds cut in this shape to display their glitter and brilliance. And the brilliant- which both reflects and splits light- is still the best cut shoeing off a precious stone?s fire.

LUCKY STRIKE

In 1903, blacksmith Fred La Rose, of captain, Ontario, in Canada, threw his hammer at a marauding fox, missed ?and struck silver. The hammer landed on what turned out to be the world?s richest vein of silver. La Rose sold for $30,000- and by 1913 the vein had yielded silver worth $300 million.

BURYING MANHATTAN

In most modern gold mines, miners have to dig tones of rock to find ounces of gold, and they generate mountains of waste rock in the process. If the 50 million tones of waste from just one gold mine, the Randfontein, near Johannesburg, South Africa, was spread out evenly, it would bury the whole of New York?s Manhattan Island, an area of 57km2 (22 square miles), to a depth of 2.4 m (8ft).

CARDLE OF INDUSTRY

Coalbrookadale, in the heart of England, was uniquely equipped by nature to become in the 18th and 19th centuries the iron cradle of the world?s first industrial revolution. The town is built on an unusual sequence of rocks that includes layers of clay (used for making pottery and brick for furnaces), coal, ironstone and limestone, ironstone and coke (a high- carbon fuel made from coal) were the essential ingredients for making iron.
Percolating through part of the rocks was strange treacle material- natural bitumen ? that in the 18th century was burnt or used to make oils for lubricating machines and wheel axles. Ti, too, came to have an industrial role-to seal the wooden boats used to transport the iron.
MINI- MINERS

Microbes are now being used throughout the world to leach miners from rocks. One of the most widely used microbes is Thiobacillus, which has successfully extracted sulphur, copper, and nickel. The microbes placed in a bath crushed rock and liquid; trigger a series of complex reaction which results in the metal being dissolved in the liquid. It can be extracted from the solution by traditional chemical processes.
A similar technique, the mini-miners are used only to work low- grade ores, or ores that are inaccessible, or unworkable or uneconomical to recover by conventional means. But it seems likely that their use will grow as biologists find more and better ways of putting them to work.

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