Diamond
4 of the 7 encyclopedias on this shelf carry an entry for Diamond. Both are reproduced below, so you can see where they agree and where they differ.
Collier's New Encyclopedia (1921)
2026 Editor's Note: This page uses language about race that was commonplace when the book was published and is offensive by today's standards. The text has been left exactly as it was printed, rather than cut or softened, so that the historical record — including how ordinary such language once was — is preserved. (Ed: ET 2026-07-22) a natural form of carbon, highly valued as a precious stone when transparent and of the crystalline form. 3 DIAMOND CUTTING 4. Brilliant cutting-top 5. Brilliant cutting-side 6. Brilliant cutting-back view A diamond crystallizes in the cubic or monometric system, its common form being the regular octahedron or a modification of it. The bases are often curved and the general form of the crystal is more or less rounded. The surface of the diamond frequently exhibits striæ and triangular impressions, while the interior may contain microscopic cavities and various inclusions, often black carbon. It is the hardest substance known; but in spite of this hardness it is very brittle and cleavable; specific gravity, 3.52. It is generally colorless, but sometimes tinged pink, red, orange, yellow, green, blue, brown, or black. Blue, red, and green are exceedingly rare colors. Light yellow, straw, and brown are the most common colors; rich yellow and browns are also highly prized. Some bluish-white Brazilian diamonds are phosphorescent in the dark after exposure to the sunlight. Originally diamonds were preserved in their natural form, but in 1456 Louis de Berguin of Bruges discovered the art of polishing them on rotating disks with diamond dust. These circular disks, about 10 meters in diameter, are at the present time of soft steel covered with diamond dust and oil, and made to revolve at 3,000 revolutions a minute. This gives the diamonds the artistic smooth surfaces and sharply defined edges. The process is slow and tedious, and requires great skill to produce fine results. Until a few years ago Amsterdam was the great diamond-cutting center of the world, but the finest cutting is now done in the United States, and in a great measure by machinery. As to the cutting process: Diamonds are, first, cleaved; that is, along the line of cleavage of the stone a tiny cut is made by rubbing the stone with another diamond at the point where it is desired to cleave it, then a dull knife-edge is placed in the cut, and a sharp blow will separate the stone on a cleavage plane. Secondly, diamonds are cut by rubbing two diamonds together, the stones being cemented with shellac to two pieces of wood or handles which are held in the hands, and rubbed together till they are of the desired form. This also has been superseded partly by an American machine. Diamonds of from 1 to 22 carats each have been found in 24 localities in the United States, mapped by Kunz for the United States Geological Survey. The combustibility of diamonds was proved in 1694 by Averani and Targioni with the aid of burning glasses. That diamonds turned to carbonic acid when burned was proved by Lavoisier in 1772. In 1867, in the S. of Africa, John O'Reilly, a trader and hunter, reached the junction of two rivers, and stopped for the night at the house of a farmer named Van Niekerk. Children were playing with some pebbles they had found in the river. O'Reilly took one of these pebbles to Dr. Atherstone, at Cape Town, who said that it was a diamond of 22/½ carats. It was sold for $3,000. Niekerk remembered that he had seen an immense stone in the hands of a Kaffir witch-doctor, who used it in his incantations. He found the man, gave him 500 sheep, horses, and nearly all he po3sessed for the stone, and sold it for $56,000. This was the famous "Star" of South Africa. It weighed 842 carats in the rough, and was found to be a gem quite the rival of an Indian stone in purity and brilliancy. After it had been cut it was bought by the Earl of Dudley, and is now known as the Dudley diamond. By 1869, parties in ox-wagons had worked their way over the plains to the Vaal river. Soon a tented city of 12,000 or more foreigners grew at Pniel and Klipdrift, on the opposite banks of the stream, where diamonds were found plentifully. The mines at Kimberley, 600 miles from Cape Town, are the richest in the world. The output of a single mine, the "Kimberley," is $4,000,000 annually, and within 10 years this district has yielded about $58,000,000 in dividends. Ninetyfive per cent. of all the diamonds produced in the past 20 years came from South Africa. Most of the miners are natives, who are kept in compounds for periods of from three to six months; this system has broken up the illicit diamond buyers' ("I. D. B.") system, which seriously threatened the successful working of the mines. The life chairman of this syndicate was the Rt. Hon. CECIL J. RHODES (q. v.), who by his genius and will created the corporation apparently out of chaos. The buying and selling of the gems is controlled by the government. The total value of all the diamonds known to exist in the world to-day is at least $1,000,000,000. It may safely be said that one-third of all the diamonds one-third known are owned in the United States. Most of the great diamonds distinguished for beauty and size have very interesting histories. One of the most famous is the Koh-i-Nûr, or Koohinoor, "Mountain of Light." The legend is that it was carried 5,000 years ago by the hero Karna, whose deeds are celebrated in the "Mahabharata." It made its first appearance in history in the 14th century, when Ala-ed-din brought it to Delhi. At that time it was supposed to weigh 793 carats. When in 1673 the Grand Mogul sold it to Tavernier, it weighed only 279 carats, having been injured by the lack of skill of a Venetian lapidary. It was brought in 1739 at the sack of Delhi to Afghanistan. Thence it came into the possession of the East India Company, which presented it in 1850 to the English Crown. It was re-cut in 1 2 3 4 1. Southern Star 2. Southern Star 3. Great Mogul 4. Florentine 5 6 7 8 FAMOUS DIAMONDS 5. Koh-i-Nûr 6. Koh-i-Nûr (new cutting) 7. Regent or Pitt 8. Orloff 1852 and now weighs 100 1-16 carats. What was at the time said to be the largest stone in the world was sent to London from the Jagersfontein mines in South Africa in 1893. It weighed 971 carats, or nearly half a pound. Another weighed 640 carats. Another important diamond was set in the poit of the scepter of the Russian empire, known as the Orloff, which weighs 194% carats. One time it formed the eye of an idol in the temple of Seringham in Mysore, whence stolen. It his murder it was bought by an Armenian merchant in 1772 at the price of 450,000 silver rubles and the title of nobility. By the gift of Prince Orloff, a favorite of Catherine II., from whom it derived its name, it came into her possession. The supposed great diamond of the King of Portugal, 1,770 carats, is mythical; or rather is a rolled oval pebble of white topaz. The Regent or Pitt diamond weighs 136.75 carats, and is of the purest water and most perfect shape. It decorated the sword hilt of Napoleon I., and is now in the Galerie d'Apollon in the Louvre. One of the finest of diamonds is the Sancy diamond, 53½ carats, of exquisite shape and perfect water. It has be been traced back to Charles the Bold, who lost it in 1477 at the battle of Nancy. It came_through many private hands to the Huguenot nobleman Sancy. When Sancy was sent as an ambassador to Solothurn, he received from Henri III. the command to send to him that diamond as a pledge. The servant to whom it was intrusted was attacked and murdered, but instead of giving up the diamond he swallowed it. Sancy had the body opened and found the precious diamond in his stomach. James II. procured it when he came to France in 1688. Later it came into the possession of Louis XIV. and was worn by Louis XV. at his coronation. One of the most superb diamonds known is the sapphire-blue brilliant Hope diamond, valued at about $100,000. It is believed to have been cut from a blue diamond weighing in the rough 112½ carats, sold by Tavernier to Louis XIV., and which disappeared in the troubles of 1792. The largest diamond ever found in Brazil weighed 2542 carats, and was discovered in 1853 by a negress in the river Bogageno; it is known as the "Star of the South." It was sold to the Gaekwar of Baroda for $450,000. The largest and finest diamond in the world to-day was cut from the Cullinan crystal found in the Transvaal in 1905, which weighed in the rough 3,106 metric carats. The largest stone cut from it "The Star of South Africa" weighs 530.2 carats and was presented to King Edward VII. by the Union of South Africa. The diamond weighing method was changed in 1910. The standard "metric carat" is of 200 milligrams divided into hundredths, conforming with the metric system. The United States adopted the new carat July, 1913. DIAMOND BEETLE (Entimus imperialis), splendid coleopterous insect bein the throne of Nadir Shah, and after longing to the family Curculionidæ. It it a native of South America.
Aiton's Encyclopedia (1910)
a precious stone. A form in which pure carbon occurs in nature. As a stone it is a crystal, generally without color, but found also in many tints and colors as blue, red, green, black, light yellow, straw, brown, pink, and orange. The diamond is the hardest substance known. It cannot be scratched by anything but a diamond. It cannot be dissolved by any known liquid nor melted under any attainable degree of heat. Any one who can afford to do so can burn a diamond, like a piece of coal, in oxygen. It consumes without ashes, giving off a brilliant light. When heated in a voltaic arc it crumbles into black lead. Diamond dust is used in the arts to cut and polish gems. The edge of a diamond is used to cut glass, or rather in producing a scratch along which the glass breaks readily. A sharp diamond point is used in engraving on glass and steel, and, when set in a lathe, for turning glass lenses. Cheap diamonds are used in the diamond drill in making holes for blasting rocks. As no tool will cut a diamond, the earliest method of dressing diamonds was that of grinding two diamonds together until the desired face had been formed. Under present methods, chips are split off until the stone approaches the desired shape. The faces are then held against a whirling disk of steel fed with oil and diamond dust, and rotated at a rate of 2,000 to 3,000 revolutions per minute. This method of polishing was hit upon shortly before the discovery of America. The chips are saved for many purposes. Diamonds are cut into various shapes. The table stone is a flat slab-shaped gem with beveled edges. A rose diamond has a flat, circular, or elliptical under surface or base. Its upper surface consists of twelve or more triangular faces or facets, the uppermost of which come together in a point at the center. A third shape, the brilliant, gives the most sparkling effect. It is cut with facets on both the under and the upper surface. The top and back, however, terminate in flat facets instead of points. Counting these two central faces, the upper part of a regular brilliant has thirty-three faces and the lower part, or back, has twenty-five, making fifty-eight in all. Golconda, India, was long a center of gem cutting. Amsterdam in later times has been the great European diamond cutting center. One Amsterdam establishment claims to cut and polish 400,000 diamonds yearly. America is the great retail diamond market of the world. About $525,000,000 worth, or one-third of the world's diamonds, are owned in the United States . Of late improved methods connected with the introduction of machinery have given American jewelers a claim to superiority in cutting as well. During the year of 1905 $36,060,000 worth of diamonds and other precious stones were imported into the United States. Diamonds are widely distributed in nature. Small ones are found in a score of localities in the United States. The most ancient source of supply is India. In 1728 diamonds were found in Brazil, in 1829 in the Ural Mountains , and in 1867 the rich South African diamond fields began to attract attention. The richest diamond mines in the world are at Kimberley, South Africa, where a group of mines owned by a syndicate yields from ten to twenty million dollars' worth annually. Diamonds occur in the shape of pebbles in beds of gravel, and are found by washing the earth. It is not uncommon for a diamond to explode on reaching the surface. Some have been known to explode in the pockets or in the warm hands of the miners. The larger the diamond the more likely it is to fly into pieces. Large gems are sometimes imbedded in a raw potato as a protection against explosion. Diamonds are weighed by the carat, 151.76 of which equal an ounce Troy. A perfect gem of a pure white without flaw is called a diamond of the first water. Small artificial diamonds have been made by allowing carbon in molten iron to crystallize under high pressures, such as running the molten metal into a mold and cooling it quickly in cold water. One of the most noted diamonds is the Kohinur or "Mountain of Light." After passing through various vicissitudes, including the sack of Delhi, it came into the possession of the East India Company , by whom it was presented to the English crown. It has been reduced by successive recuttings, the last in 1852, to a weight of 106.16 carats. The Orloff diamond forms the point of the royal scepter of Russia. It is a fine rose diamond, weighing 194 3/4 carats. It was at one time the eye of an Indian idol at Mysore. Prince Orloff bought it through an Armenian merchant in 1772 for 450,000 silver roubles, and presented it to Queen Catharine of Russia. The Regent or Pitt diamond is also from India. It weighs 136 3/4 carats, and is considered one of the most beautiful gems in existence. It is guarded as one of the treasures of the Louvre in Paris. Of late astonishing finds have been made at Kimberley. The mine is 640 miles from Cape Town , a ride by rail of two days and one night. The mine itself is the crater of an extinct volcano. The general surface of the country is level. The crater is about 312 feet deep. Diamonds were found in the gravel. Workmen have dug 300 feet lower, so that the mine is now 612 feet deep. A blue rock is lifted to the surface by powerful machinery, and spread out on the grounds to dry. In the course of a year, under the influence of the sun, rain, and winds, it decomposes and falls apart. It is then crushed, washed and sifted, and passed finally over shaking tables, covered with a certain sort of grease that catches and retains the diamonds. These are then washed in an acid, sorted, valued, and sold to a syndicate. One thousand tons of blue rock yield 500 pounds of diamonds. The company employs 15,000 natives and 25,000 whites. Two hundred thousand horses are worked. A town of 35,000 people has grown up at the mine. At the end of 1904 it was estimated that diamonds worth $300,000,000 had been shipped from Kimberley. These gems would fill a box five feet square and six feet deep. The largest diamond produced at the Kimberley mine is one now known as the Syndicate. It weighed 960 carats in the rough. It is owned by Tiffany of New York . The largest diamonds ever known have been found recently in the Premier mine at Johannesburg, South Africa. In March, 1905, a huge gem was found which was named the Culinan diamond. It weighed, uncut, 3,251 carats, or over a pound and a half. It was presented by the Transvaal government to King Edward. It was valued at $2,500,000. It has been split to form two large gems. These are known as Culinan I and Culinan II. They weigh 516 1/2 and 309 3/16 carats respectively. A second gem found since in the same mine weighs 460 carats. It is four times as large as the famous Kohinur. It is practically flawless. It is valued at $1,500,000. See Carbon ; Coal 2026 Editor's Note: For the diamond's full story as this era knew it — Kimberley, the syndicate, the great stones — see our companion site, A Book of Precious Stones (1909), annotated like this one. (Ed: BR 2026-07-08)
The Encyclopedia of Founding (1892)
Important: Safety Warning This page contains a formula or preparation using substances now known to be dangerously toxic, such as arsenic, mercury, lead, or cyanide compounds. Exposure to these substances can cause severe poisoning, permanent injury, or death. In addition, this page describes trade processes that use dangerously toxic materials such as cyanide solutions, mercury amalgams, or strong acids. These processes require training, equipment, and precautions far beyond what the text describes. This information has been left in for historical purposes but should not be acted upon. The purest form of carbon known. It is a crystal of the greatest purity and hardness known. Several localities in India, the island of Borneo, and Brazil furnish this beautiful substance. Diamonds possess a very high refractive and dispersive power, by which they flash the most varied and vivid colors of light. The diamond is a non-conductor of electricity, and resists the action of all known chemical substances. It is infusible and unalterable even by a very intense heat if air be excluded; but when burned in oxygen gas, the combination forms carbonic acid gas, hence its composition is pure carbon. Heated to whiteness in a vessel of oxygen it readily burns, yielding carbonic-acid gas; hence its composition is pure carbon (specific gravity, 3.5). A diamond is of the first water when perfectly colorless. Artificial diamonds are made from a paste composed of pure silica 100, red oxide of lead 150, calcined potash 29, calcined borax 11, arsenious acid 1. This composition fuses at a moderate heat, and if the alkali is expelled by the continued fusion it acquires great brilliancy. See PRECIOUS STONES; CARBON.
An Encyclopaedia of Occultism (1920)
This gem possesses the most marvellous virtues. It gives victory to him who carries it bound on his left arm whatever the number of his enemies. Panics, pestilences, enchantments-all fly before it; hence, it is good for sleepwalkers and for the insane. It deprives the lodestone of its virtue, and one variety, the Arabian diamond, is said to attract iron more powerfully than the magnet itself. The ancients believed that neither fire nor blows would overcome its hardness, unless macerated with fresh goat's blood; and Cyprian, Austin, Isidore, and others of the fathers, adopting this notion, have used it to illustrate the method by which the blood of the Cross softens the heart of man. If bound to a magnet, the diamond, according to the belief of the ancients, will deprive it of its virtue.