Lapia-lazull, or azure-stone, from Central Asia, is not in much request in India. It was the sapphire of Pliny. It is found in High Asia and in China provinces. In ancient times it was used for cameos and intaglios. The Chinese make it into cups, vases, buttons, caskets.
Malachite, an imported mineral, is rarely worn, and only by Europeans. It occurs in the copper mines in Australia, also largely in Russian provinces.
Mother of Pearl is the nacre from the interior of the shells of molluscs, chiefly from that of the Meleagrina margaritifera.
Onyx, a quartzoso mineral, is so named because of its substance being in layers of two colours, as on the nail of the human hand. One of the layers is white, tho other of a greyish tint. In its natural state it is a sober mineral, but it is stained black by being boiled in honey, oil, or sugared water, and then in sulphuric acid. For red, protosulphato of iron is added ; and for.
hlue, iron.
of putaeh is gilded to the probe sulphate of ron.
tiral bee as varieties the Mexican tire opal, the noble opal of I fuegary. Preeknu opal le the tweet beautiful of all genie. Its price depends, on the play of colours displayed. The hydrophine or opal loses Its beauty when cep need to water.
Common Opal, of a dull white without any play of colours, occurs massive in the volcanic tract of the Dekhan. It is used as a charm round hones' necks, and by native dentists for false teeth.
Oriented is a term employed by jewellers to deeignate precious stones of the highest value. It is now excluded from books of mineralogy, the minerals to which it was formerly applied being now-a-days noticed under their chemical composition.
Pearls occur of all colours. Those of Asia, from the sea pearl oyster, Meleagrina margaritifers, are found on the west coast of Ceylon, in the gulf of Manaar, in Ilse Pei-shin Gulf, in the Sulu Islands, near New Guinea, and in the Red Sea. Off the coast of Ceylon, the fish ing season is inaugurated by numerous ceremonies, and the fleet, sometimes of 150 boat., then put to sea. Each boat has a stage at its side, and is manned by teu rowers, ten divers, a steersman, and a shark charmer (pillal karma). The mon go down five at a time, each expediting his descent by means of a stone 20 to 25 pounds in weight, and holding their nostrils ; they gather about 100 shells in the minute which they remain under water. Each man makes 40 to 50 descents daily. The pearl oysters aro thrown on the beach and left to putrefy. In the I'ersian Gulf, so many as 30,000 persons are said to be employed in the pearl fishery (Job xxviii. 18). According to European taste, a perfect pearl should be round or drop-shaped ; of a 1 pure white, slightly transparent ; free from specks, I spots, or blemish, and possessing the peculiar lustre ' characteristic of the gem. In India and China, the bright yellow colour is preferred. Cleopatra is fabled to have dissolved in vinegar a pearl of the value of 150,000 aureas or golden crowns, in the presence of Anthony, and to have drunk it off ; but it would have required a larger quantity and stronger acid than any one could have taken with impunity, to have done so.
Caesar is said to have paid a sum equal to £50,000 sterling for a single pearl. The fellow-drop to the pendant destroyed by Cleopatra is said to have been sawn in two by command of the emperor Augustus, and used to adorn the statue of Venus. The mother of the last nawab of the Carnatic gave him is necklace of pearls, each of which cost about Rs. 1000.
Quartzosc minerals are largely used for personal ornament, far articles of luxury, and in the decorative arts. They have been skilfully adapted in the orna mentation of the beautiful Taj Mahal at Agra. Those better known to jewellers and lapidaries are sometime, designated inferior gems, such as the agate, amethyst, bloodstone or heliotrope, chrysoprase of an apple-green colour, carnelian.• jasper and Egyptian jasper, onyx, common opal, plasma, rock-crystal, hard, and sardonyx. The lust is rarely seen in India. Jasper, onyx, comma, opal, bloodstone or heliotrope are (mod to abundance in many parts of the Dekhan, in the valley of the Gods very, and amongst the Cambay stones. Mocha-stones and moss-stones of great beauty occur among the minerals from Cambay. Cambay enjoys celebrity fur its agates, mocha-stonee, carnelian*, and ill the chalce donic and onyx family. MI of them are brought from Itajpipla, but worked up at Cambay into every variety of ornament,—eups, boxes, necklace., handles of dagge ri, of knives and forks, seals, etc. They are from the nmygdaloid trap rocks drained by the Nerbadda and Tspti. The principal varieties sold in Bombay are crystal, milk quartz, prase, a green variety of mom stone, mocha - stone, fortification agate, calcedony, carnelian, chrysoprase, heliotrope, onyx, obahlian, and very rarely amethyst. These stones abound in all trap countries, the Brazils exporting them as largely as India into Europe, where the terms Brazilian and Indian agates are used indifferently by the trade. lioek-rrystal is abundant in the south of the Peninsula of India at Vellum. It can be dyed. If made red-bot, and plunged repeatedly into the tincture of cochineal, it becomes a ruby ; if into a tincture of red sandal, it takes a deep red tint ; into tincture of saffron, • yellow like the topaz ; into a tincture of turnesol, a yellow like the topaz ; into juice of nerprum, it takes a deep violet like the amethyst ; and into a mixture of tincture of turnesol and saffron, it becomes an imitation of the emerald. Steeping the crystal in oil of turpentine saturated with verdigris or spirits of wine, holding dragons' blood or other coloured resins in solution, depths of tints are produced proportioned to the time of steeping. Crystal can be coloured if heated in a crucible with orpiment and arsenic. Crystal coloured red, as false rubies, are known in France as rubaces.