A large ruby is more valuable than a large diamond, weight for weight. Some experts affirm that a five-carat ruby is worth ten times as much as a five-carat dia¬mond. Certainly an eleven-carat ruby has been known to fetch £7000 sterling, while an eleven-carat diamond is estimated at only £1000 sterling in value. These were pre-war prices.

Rubies are found in Ceylon, Borneo, Kashmir, Siam. Afghanistan, Montana in the United States, and New South Wales, but only a few come from any of these places. The bulk of the rubies in commerce come from Mqgok, ninety miles north-east of Mandalay, the capital of Burma.

For three hundred years the Burmese kings, who loved the ” pigeon-blood ” stones, as they called them, owned the area of land upon which the rubies were found. The possession by any private individual of a ruby worth more than £70 was a crime, and the ruby-fields were forbidden ground to the stranger. Since Great Britain annexed Burma in 1885 these ruby-fields have been worked by an English company, on lease till 1932. The most valuable stone found here weighed 77 carats.

The best known and most popular of the corundum gems are ruby and sapphire ; and they are usually found close together.    The ruby is the rarer of the two and therefore more valuable. The price per carat of the sapphire is independent of the size of the gem, but the larger rubies fetch a much higher price per carat than the small ones. Rubies and diamonds are always associated together as the most precious of stones. Thus Dry den sings :

“His ample forehead bore a coronet With sparkling diamonds and with rubies set.”

Palamon and Arcite, iii. 54.

The Gaekwar of Baroda has a coat woven of gold and embroidered with diamonds and rubies which cost £25,000 sterling; the Emir of Scindia possesses a bril¬liant scarlet coat and a cap of black and gold studded with rubies and diamonds costing over £30,000 ; and many other Eastern potentates possess similar collections.

The Oriental ruby, sapphire, emerald; chrysolite, topaz and amethyst are all varieties of corundum, a mineral which is only inferior to the diamond for hard¬ness, and is found in crystalline limestone (e.g. in Burma), and in alluvial sands and gravels derived from igneous and metamorphic rocks.

When coloured, as in the case of all the varieties mentioned above, it shows a striking dichroism, being deeply coloured when viewed along the direction of the vertical axis and pale coloured when viewed at right angles to this direction. Hence the red variety, the Oriental ruby, can be distinguished by this experiment from the garnet, the Balas ruby (found in Bokhara) and the Spinel, which are cheaper, more common and more brittle, and are not corundum gems. Read the rest of this entry »