On the 27th of January 1905, the largest diamond in the world, weighing 30254 carats, over 12 lb avoirdupois, was found in the mine and named the Cullinan.
The output was about 90,000 carats in 1917 and over 200,000 carats in 1920.
The amount of gold in 1000 parts of alloy; (2) as " carats," i.e.
In England the following standards are used for plate and jewelry: 375, 500, 62 5, 75 0 and 916.6, corresponding to 9, 12, 15, 18 and 22 carats, the alloying metals being silver and copper in varying proportions.
And was subsequently cut into two stones, one of 5162 carats, the other of 309 carats, intended to ornament the sceptre and crown of England.
The opal was mined here Boo years ago, and the largest piece hitherto found, weighing 2940 carats and estimated to have a value of £175,000, is preserved in the Court Museum at Vienna.
Like all the precious stones, the diamond was credited with many marvellous virtues; among others the power of averting insanity, and of rendering poison harmless; and in the middle ' Diamonds are invariably weighed in carats and in z, 4, a, 1, s, of a carat.
Rock drilling is the most important industrial application; and for this, owing to its freedom from cleavage, the carbonado is more highly prized than diamond; it is broken into fragments about 3 carats in weight; and in 1905 the value of carbonado was no less than from £10 to £14 a carat.
The old mines have now been completely abandoned, but in 1891 about moo carats were being raised annually in the neighbourhood of Hyderabad.
India was no doubt the source of all the large stones of antiquity; a stone of 67* carats was found at Wajra Karur in the Chennur group in 1881, and one of 2102 carats at Hira Khund in 1809.
The diamond here occurs in river gravels and sands associated with the same minerals as in Minas Geraes; since 1844 the richest mines have been worked in the Serra de Cincora, where the mountains are intersected by the river Paraguassu and its tributaries; it is said that there were as many as 20,000 miners working here in 1845, and it was estimated that 54,000 carats were produced in Bahia in 1858.
In 1869 a stone weighing 83* carats was found near the Orange river; this was purchased by the earl of Dudley for £25,000 and became famous as the " Star of South Africa."
African mines the diamonds are not only crystals of various weights from fractions of a carat to 150 carats, but also occur as microscopic crystals disseminated through the blue ground.
In 1905 the year's production from the Orange River Colony mines was more than 320,000 carats, valued at £938,000.
The large Borneo stone, over 360 carats in weight, known as the Matan, is in all probability not a diamond.
At Mount Werong a stone weighing 29 carats was found in 1905.
A crystal weighing 23* carats was found in Virginia in 1855, and one of 214 carats in Wisconsin in 1886.
The following are some of the most famous diamonds of the world: - A large stone found in the Golconda mines and said to have weighed 787 carats in the rough, before being cut by a Venetian lapidary, was seen in the treasury of Aurangzeb in 1665 by Tavernier, who estimated its weight after cutting as 280 (?) carats, and described it as a rounded rose-cut-stone, tall on one side.
It weighs 1944 carats, is of a somewhat yellow tinge, and is among the Russian crown jewels.
The Regent or Pitt diamond is a magnificent stone found in either India or Borneo; it weighed 410 carats and was bought for £20,400 by Pitt, the governor of Madras; it was subsequently, in 1717, bought for £80,000 (or, according to some authorities, £ 135,000) by the duke of Orleans, regent of France; it was reduced by cutting to '3614 carats; was stolen with the other crown jewels during the Revolution, but was recovered and is still in France.
The Akbar Shah was originally a stone of 116 carats with Arabic inscriptions engraved upon it; after being cut down to 71 carats it was bought by the gaikwar of Baroda for £35,000.
The Nizam, now in the possession of the nizam of Hyderabad, is supposed to weigh 277 carats; but it is only a portion of a stone which is said to have weighed 440 carats before it was broken.
The Great Table, a rectangular stone seen by Tavernier in 1642 at Golconda, was found by him to weigh 242 1 - 3 6 - carats; Maskelyne regards it as identical with the Darya-i-nur, which is also a rectangular stone weighing about 186 carats in the possession of the shah of Persia.
Other famous Indian diamonds are the following: - The Sancy, weighing 53 carats, which is said to have been successively the property of Charles the Bold, de Sancy, Queen Elizabeth, Henrietta Maria, Cardinal Mazarin, Louis XIV.; to have been stolen with the Pitt during the French Revolution; and subsequently to have been the property of the king of Spain, Prince Demidoff and an Indian prince.
The Nassak, 788 carats, the property of the duke of Westminster.
The Empress Eugenie, 51 carats, the property of the gaikwar of Baroda.
The Pigott, 49 carats (?), which cannot now be traced.
Coloured Indian diamonds of large size are rare; the most famous are: - a beautiful blue brilliant, 67126 carats, cut from a stone weighing 112 i carats brought to Europe by Tavernier.
The Hope, 444 carats, has the same colour and is probably a portion of the missing stone: it was so-called as forming part of the collection of H.
Two other blue diamonds are known, weighing 13* and 14 carats, which may also be portions of the French diamond.
The Dresden Green, one of the Saxon crown jewels, 40 carats, has a fine apple-green colour.
The Florentine, 1331 carats, one of the Austrian crown jewels, is a very pale yellow.
The most famous Brazilian stones are: - The Star of the South, found in 1853, when it weighed 2542 carats and was sold for £40,000; when cut it weighed 125 carats and was bought by the gaikwar of Baroda for £80,000.
Also a diamond belonging to Mr Dresden, 119 carats before, and 762 carats after cutting.
The most famous are the following: - the Star of South Africa, or Dudley, mentioned above, 832 carats rough, 462 carats cut.
The Stewart, 2888 carats rough, 120 carats cut.
The Victoria, 180 carats, was cut from an octahedron weighing 4572 carats, and was sold to the nizam of Hyderabad for £400,000.
The Tiffany, a magnificent orange-yellow stone, weighs 1252 carats cut.
A yellowish octahedron found at De Beers weighed 4282 carats, and yielded a brilliant of 2882 carats.
Some of the finest and largest stones have come from the Jagersfontein mine; one, the Jubilee, found in 1895, weighed 640 carats in the rough and 239 carats when cut.
It weighed 971 carats, and was ultimately cut into ten stones weighing from 68 to 13 carats.
This extraordinary diamond weighed 30254 carats (13 lb) and was clear and water white; the largest of its surfaces appeared to be a cleavage plane, so that it might be only a portion of a much larger stone.
The four largest stones weigh 5162 carats, 309 T% carats, 92 carats and 62 carats respectively.
From the use of gold and silver as a medium of exchange, it followed that they should approximate in all nations to a common degree of fineness; and though this is not uniform even in coins, yet the proportion of alloy in silver, and of carats alloy to carats fine in gold, has been reduced to infinitesimal differences in the bullion of commerce, and is a prime element of value even in gold and silver plate, jewelry, and other articles of manufacture.
The first diamond, a stone of 50 carats, was found in August of that year, and digging immediately began.
Basing the calculation on the figures for the ten years 1896-1905, the average annual production is slightly over two and a half million carats, of the average annual value of £4,250,000, the average price per carat being £1: 13: 3.