A TABLE

OF

FRECIOUS STONES OF THE FIRST AND SECOND ORDERS.

ORDER FIRST*.

Clafs first.

f1. THE DIAMOND.

The ADAMAS of both ancients and moderns. HARDNESS from 20 to 18; SPECIFIC GRAVITY from 4,4 to 3,2%

Varieties.

WHITE, PINK, BLUISH, YELLOW, CUBIC, GREEN, BLACK.

[N.B. Cut green diamond must be very rare, as it flies to pieces when applied to the turning lathe, like the lachryma Batavica, so often shown in classes of natural philosophy.]

The DIAMOND burns away, and leaves but little soot; but it is found to be of an unknown earthy nature. By some late experiments, there is reason to believe that the diamond is composed of a particugas and water; but here some farther elucidations are still wanted.

lar

*The Editor has been favoured with the following notices concerning the gems &c. found in Scotland, by a gentleman who has made that branch of science a particular study.

3

§2: THE JARGON, OR ADAMANTINE SPAR OF CEYLON:

HARDNESS 16; SPECIFIC GRAVITY 4,4.

Varieties.

The JARGON formerly known, was either white, yellow, or brown. The new varieties are greenish, with the splendour of silver; or dark grey, with that of pinchbeck.

Analysis.

JARGON H 16; Sp Gr 4,4; New Earth 68; Sil 3; Ir and Nikel ; KLAPROTH of Berlin.

There are but few of the gems that are not found in Scotland; and as for the more common stones, such as agates, jaspers, granites, porphyries, c. there is no place in the world that has a greater variety.

The diamond has never been found in Scotland. The Sapphire has been found in several places in the Highlands of Scotland, of different shades, from a deep to a perfect clear transparent white, and equal in hardness to the oriental sapphire. The Topaz is also found in most places of the Highlands, of various fhades, from almost an orange, to a pale straw colour, and are commonly called Caringarom stones, being the place where' most found. Mr Farquharson of Invercauld has the largest ever found in Scotland, and which was got upon his own ground. It is as large as the body of a child of two years old. None is found with more or less than six sides. The nearest to the Hyacinth found in Scotland, is the Ely Ruby, so called by the people of Ely in Fife, which, when polished, is very beautiful. This is found amongst the sea sand. Part of the rocks under the sand is stuck full of this stone; but none of them are got of any size and clean.

The Emerald, and Aqua Marine are found in several places of the Highlands. The amethyst also. Some are found of a very large size, and good colour :-the largest polished one I have seen, was upwards of an inch over, every way, and proportionally cut, which was sold for forty guineas :—I have seen another, much the same size, but paler in the colour, valued at thirty guineas, which is in the possession of lord Napier, and has a portrait of one of the ladies of his family cut upon it.

Pearls are found in a long fhaped fresh water muscle, [mytilus, cygnus, and anatinus,] in the most part of every fresh water river in the north of Scotland; and have been fished to great advantage, until prohibited by the proprietors, as encouraging idleness among the lower clafs of people. This

Form.

The diamond is most commonly octoedral, though sometimes rhomboidal, cubic, or dodecaedral. Jargon, or soft diamond, as it was formerly called, we were told is found in a dodecaedral, or in a pebble form, split into thin plates in India, and sent to Europe in that form; but the same stone, under the name of the adamantine spar, is said lately, by Mr Born, to

fhell fish is called the borse muscle:-some of these pearls were of great size; they are frequently found in the common sea oyster: in one oyster I found five pearls of different sizes. They are often found in the common muscle, but of a small size.

The Garnet is found in great quantities in the Highlands, some as large as a walnut.

There is also found at Portsoy, most beautiful Granite, which takes a fine polifh; at first sight one would take it for Hebrew characters. The spotted Jaspers found on Arthur's Seat are singular, as none of the kind have ever been known to be found any where else.

A few of the fossils found in Scotland, are, a great variety of curious earths; mica, talcs, lapis specularis; great variety of granites; great variety of porphyries; great variety of jaspers of all colours; garnets imbedded in granites; garnets in micaceous stones, from Inverary; garnets in clusters, from Portsoy, containing iron and tin; great variety of fhorls imbedded in quartz; bar fhorls, pointed fhorls; variety of red unfigured zeolitus mineralized; great variety of asbestus; great variety of variega-. ted amianthus; variety of fasciculated amianthus ; variety of zeolitus plumosus; variety of amianthus flexuosa, or crooked amianthus; variety of iron ores, grey and black cobalt ores; Glunetz cobalt ores with silver; red, green, and yellow cobalt ores; mountain green copper ores; white copper ore; with a vast variety of cobalt and silver ore, lead, bismuth, &c. The eyed pebbles found in Scotland are most beautiful; there is scarce ly any thing like them found any where else.

The green jasper, or blood stone, from Icolmkiln island, is found in large blocks, and is a beautiful stone, which engraves well, and answers well for seals.

The chalcedony, or white cornelian, found in Fife, is equal to those from the East Indies for colour, and are the same hardness.

N. B. Those mentioned in the table which are marked thus are found Scotland.

be found in Ceylon, under the singular form of octoedral prisms, separated by an intermediate prism; and that he is in doubt if he fhould clafs it here, or as a white hyacinth; whilst Klaproth mentions it under the name of zirkan, as found in small prisms, fat to the touch, and only sometimes transparent.

Structure, Properties, &c.

The DIAMOND. Texture lamellar or foliated, like all the rest of the finer transparent gems; that is to say, composed of thin hard plates, strongly adhering together. Electric on friction, and phosphoric in the dark.

The JARGON approaches the nearest in colour to the diamond; in so much, that some jewellers have been deceived, and purchased them for diamonds when set into work; though they are not much har der than chrystal, of which the jargon is only a species. It is never found of any considerable size; and always is, in its rude state, a little rounded, as if it had been rolled in the bed of a river. When unset, they have not much brilliancy; and may be distinguished with certainty from diamonds, by observing the facets, which in the jargon are always rounded. The tables never so flat, nor take so fine a polifh as the diamond.

Largest.

The largest rough diamond belongs to the king of Portugal, from the Brasils. It weighs 1680 carats, and is worth five millions and a half sterling, at the lowest calculation, This gem was still larger; but the ignorant peasant who found it, broke off a piece by a violent blow of a hammer upon an anvil, to try its hardness. The largest cut diamond adorns the sceptre

of the empress of Rufsia, weighing 779 carats : worth four millions and a half sterling. It is said to have been one of the eyes of the famous Malabar idcl, Scheringham, obtained by the stratagem of a French grenadier, who escaped with it, first to Trinchinapenty, and then to Madras, where he sold it to a captain of a fhip for 20,000 rupees. A Jew purchased it from the captain for L. 18,000 sterling; and it was no more heard of till, in 1766, it was offered for sale by a Greek merchant, Gregory Sufras, and purchased by prince Orlof for about 135,417 guineas, not the thirtieth part of its real value, who presented it to his sovereign Catherine II. The next largest cut diamond belonged to the great Mogul, weighing 279 carats, worth L. 380,800, The third belongs to the king of Portugal, worth L. 369,800, as it weighs 215 carats. The fourth to the emperor Leopold II. weighing 139 carats, worth L. 109,520. The fifth to the French king, called Pit's diamond, of 136 carats, worth L. 208,333; and he had another, called the Sancy diamond, only of 55 carats, but great brilliancy, worth L. 25,000. Black diamonds exist, although rare. The great Mogul had one of fifty-six carats

and prince Lichtenstein had likewise one, weight unknown to the author of this table.

Where found.

The diamond mines of the East Indies, towards the Gatte mountains, furnish the best and in greatest quantity, viz. Golconda, Coulour, Raolconda, Parteal, Latawan, Malacca, &c. They are also found in the island of Borneo; but at the present day, the Brasils furnish the greatest number. The jargon is