Read it through once

In our day the mines are worked upon scientific principles, under the guidance of the ablest mining-engineering talent procurable in America. There are elaborate works for reducing the blue rock and passing it through one process after another until every diamond it contains has been hunted down and secured. I watched the “concentrators” at work big tanks containing mud and water and invisible diamonds—and was told that each could stir and churn and properly treat 300 car-loads of mud per day 1,600 pounds to the car-load—and reduce it to 3 car-loads of slush. I saw the 3 carloads of slush taken to the “pulsators” and there reduced to a quarter of a load of nice clean dark-colored sand. Then I followed it to the sorting tables and saw the men deftly and swiftly spread it out and brush it about and seize the diamonds as they showed up. I assisted, and once I found a diamond half as large as an almond. It is an exciting kind of fishing, and you feel a fine thrill of pleasure every time you detect the glow of one of those limpid pebbles through the veil of dark sand. I would like to spend my Saturday holidays in that charming sport every now and then. Of course there are disappointments. Sometimes you find a diamond which is not a diamond; it is only a quartz crystal or some such worthless thing. The expert can generally distinguish it from the precious stone which it is counterfeiting; but if he is in doubt he lays it on a flatiron and hits it with a sledgehammer. If it is a diamond it holds its own; if it is anything else, it is reduced to powder. I liked that experiment very much, and did not tire of repetitions of it. It was full of enjoyable apprehensions, unmarred by any personal sense of risk. The De Beers concern treats 8,000 carloads —about 6,000 tons—of blue rock per day, and the result is three pounds of diamonds. Value, uncut, $50,000 to $70,000. After cutting, they will weigh considerably less than a pound, but will be worth four or five times as much as they were before.