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The Carbon Shown on the Opposite Page as Finally Broken into Pieces for Drills

I, Ia. Inner sides of upper part of the carbon shown as Fig. 2 in the preceding illustration. 2. The entire piece of carbon broken into pieces weighing from three to four carats each, the sizes generally used for diamond drills.

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From George F. Kunz, U. S. Geological Survey

Diamond Sawing by a Process Recently Invented by an American

The diamond is held firmly and very steadily under pressure against a rapidly revolving disk of sheet iron or "phosphor" bronze. The wheels are much like those used in sawing thin sections for microscopic rock sections or for cutting jade, rock crystal, and other hard stones. It is claimed that in thus dividing an octahedron at the center or girdle as little as 2 per cent of the weight of the crystal is lost-a great saving of material. As evidencing the wonderfully keen responsive business acumen which has always characterized the "rough" syndicate, the price of all rough diamonds that could be improved or advanced in value by such sawing was immediately advanced when the process became known.

the color and brilliancy of the gems. Sales must therefore take place between the hours of 9 and 3, and the sky must be clear.

The purchaser, placed near a window, has before him a large copper plate. The sellers come to him one by one, and each empties upon the plate his little bag of rubies.

The bright copper plate has a curious. use. The sunlight reflected from it through the stones brings out a color effect with true rubies different from that with red spinels and tourmalines, which are thus easily separated.

The buyer and seller then go through a very peculiar method of bargaining by signs, or rather grips, in perfect silence. After agreeing on the fairness of the classifications, they join their right hands, covered with a handkerchief or a flap of a garment, and by grasps and pressures, mutually understood among all these dealers, they make, modify, and accept proposals. The hands are then brought out, and the prices are recorded.

The larger single stones are valued according to color and shape for cutting, the very fine ones bringing high prices. A ruby of 361⁄2 carats from the Mogok mine some years ago brought 90,000 rupees ($30,000) at Calcutta.

Cutting is an important industry at Mandalay, and the Burmese workmen have remarkable skill, especially in avoiding loss in weight. European cutting they consider very wasteful, and at Mandalay a man would not be employed who sacrificed more than onefourth of a ruby, while at Antwerp a loss of two-thirds is not uncommon. The tools are extremely simple. The stone is first shaped with a small steel chisel and wooden mallet, as far as possible, according to its cleavage. The facets are then ground and polished on a copper wheel with ruby dust, the stone being held with wax or lac on a curved piece of ox horn. A month or six

weeks may be occupied in cutting and polishing a ruby of one carat.

The pale stones, cut rounded (cabochon) with a concave base, are much used for ornamental work, especially upon gold vessels. The luster of the gold beneath appears to enrich and darken the ruby and give it the true pigeon's-blood color.

Agates, amethysts, rock crystal, and golden topazes are shipped in great quantities from Brazil. Almost all of them go to Idar and Oberstein, in Germany, where they are cut into ornaments. Last year 200,000 pounds of agate and six tons of rock crystal were cut into seals, paperweights, and faceted stones. One wonderful geode yielded over 40,000 pounds of amethyst.

A great quantity of sapphire of a very dark blue, almost black, color, with a greenish tint, and occasionally entirely green, was imported from Australia. The tourmaline, principally the red (rubellite) and also the aquamarine from Brazil, have been sought for, and considerable quantities of both have been sold at Idar.

It is interesting to note the increasing variety of ornamental and semi-precious stones now being brought into use, and particularly the introduction of jade.

This beautiful stone has from prehistoric times been the especial favorite of uncivilized or semi-civilized peoples, and in China, Japan, and India it has yielded the choicest objects of oriental art. At the Paris Exposition of 1900 a remarkable exhibit was made of Siberian jade wrought by European artists, and now the Oceanic jade of New Zealand, long prized and carved by the Maoris, is becoming immensely popular with the civilized world.

Great bowlders of it have recently been discovered in New Zealand, in the river beds, from one of which two panels, translucent and of a rich pure green color, were cut, which were over one

yard long, two-thirds of a yard wide, and only one-eighth of an inch thick. Nearly all the jade of New Zealand was sent to Germany and there cut into stones for rings, scarf-pins, studs, and for ordinary jewelry purposes, such as those for which sard and agate have heretofore been used.

The diamond syndicate, composed of the South African mine owners, manage the sale of their diamonds very shrewdly. A purchaser must buy not only the variety of diamond he wants, but also all the other varieties from the mines. The syndicate sells its diamonds in parcels or series; each parcel is made up of the different varieties of diamonds in the proportion in which each dia

mond is found. In this way the unpopular varieties are disposed of as quickly as the popular ones.

The diamond-cutting industry in the United States has advanced very rapidly during recent years. American diamond-cutters would now be able to cut all the diamonds for this country if they could get enough rough diamonds. As it is, the rough diamonds sent over supply only one-half of the demand.

The American cutters have invented a number of new mechanical laborsaving devices, which have given them a great advantage over the European cutters, where diamond cutting is done by the ancestral “rule of thumb" handed down from father to son.

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NOTES ON PANAMA AND COLOMBIA

T is supposed by some that Panama derived its name from the native word for butterfly. Explorers of the interior tell of swarms of butterflies which at times rise on the slopes of the mountains in dense clouds, darkening the sunshine. Others maintain that the name is from an Indian word meaning abounding in fish.

The Republic of Panama is believed to have about 300,000 people, living in towns and hamlets. It extends east and west for about 450 miles, with an average breadth of 70 miles from sea to sea. Its area is about 31,500 square miles. Thus the population of the state about equals that of Washington, D. C., while its area is a little greater than the area of South Carolina. The commerce of Panama amounts to $3,000,000 per annum. These figures are supplied by the Bureau of Statistics of the Department of Commerce and Labor, and are from reports of the United States consuls at Panama and Colon, which have just been received by the Bureau and are not yet published.

The principal ports are Panama, on the Pacific coast, and Colon, on the Atlantic side, and these ports are visited annually by more than one thousand vessels, which land over one million tons of merchandise and nearly one hundred thousand passengers, chiefly for transfer over the Panama Railway, 47 miles in length, connecting the Pacific port of Panama with the Atlantic port of Colon.

Colon, sometimes called Aspinwall, has a population of about three thousand persons. It was named in honor of Columbus, who discovered the bay in 1502. The city of Panama has a population of about twenty-five thousand. It was founded in 1519, burned in 1671, and rebuilt in 1673. During the sixteenth and seventeenth centuries Panama was one of the wealthiest of the Spanish towns in the New World, as all the plunder from the Pacific coast passed through the city. It had eight monasteries, a cathedral, and two churches, a fine hospital, 200 richly furnished houses, nearly 5,000 houses of humbler sort, a Genoese chamber of commerce,

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