Chapter XIV: Value of the Diamond (3)

We will not fatigue our readers with a long dissertation on the formation of the opal. We will however, quote one theory which all may understand.

The boiling waters of the Iceland geyser are projected into the air at a considerable height, and are heavily charged with silica. As the waters fall upon the earth, large piles of earthy and stony material are formed in process of time. When these silicious masses are broken open, translucent and transparent portions of silica are found, exhibiting the colored reflections of the noble opal as long as they remain hydrated, or, in other words, as long as they retain a certain quantity of water in their composition. This observation has led M. Descloizeaux to the belief that opals found in volcanic rocks or igneous rocks have had their origin in phenomena analogous to those of the Iceland geysers. The matrix of the opal is a varied one. The gem is not only found in porcelain earth, but it occurs in fissures and seams, in what appear to be old igneous rocks. It has also been deposited in recent periods, as in the limestones of the argillaceous beds, and even in the formations of the silicious waters of the hot springs of the present time. The decomposed cement of the old Roman ruins around the hot springs of Polombieres, uniting with certain chemical properties of the waters, has changed into opal and hyalite. Trees within historic times have been transformed into opal or semi-opal; and on the island of Unja one may see blocks and trunks of trees (some even showing the marks of the hatchet) converted into opal. Silicified trees forty or fifty feet in length, may be seen stretched from Cairo to Suez. In many other parts of the world trees and plants have been transformed by the mysterious processes of nature into a silicious substance possessing the characters of opal; but none of these vegetable metamorphoses exhibit the rainbow hues to any marked degree. Quartz, when flawed in the interior, sometimes exhibits a remarkable iridescence, and may imitate the opal, especially if viewed at a distance. Such specimens of iridized quartz are called “iris,” and they may be artificially produced by a sudden blow upon the stone, or by heating it and suddenly dropping it into cold water. The superb iris ornaments worn by the Empress Josephine were of remarkable brilliancy and play of colors. In ancient and mediæval times, iridescent quartz was held in great esteem; and fine specimens mounted in antique jewelry are preserved at the present day. It is described in the “Lapidarium” of Marbodeus as follows:--

“By the Red Sea the swarthy Arabs glean
The iris, splendent with the crystal’s sheen;
Its form six-sided, full of heaven’s own light,
Has justly gained the name of rainbow bright.”

The fire opal occurs in its greatest perfection in the porphyritic rocks at Zimapan in Mexico. It is generally of a translucent hyacinth-red color and flashes forth dazzling beams of fiery carmine-red with yellow and green reflections. This Mexican gem is the most beautiful and gorgeous of all the varieties of opal; but, alas! it is also the most sensitive, and is frequently irreparably injured by water or exposure, or even by sudden atmospheric changes. So easily affected are the opals by the vicissitudes of the weather that they are almost always brighter in summer than in winter. But there are some varieties that are not so easily influenced, and are not injured by contact with water. The fact that this variety of opal is injured in course of time by contact with moisture or careless exposure is not remarkable when some of the harder gems undergo a change from similar exposure. The hard amethystine quartz, when worn as a finger ornament, will completely bleach out and become colorless in a few years. The black opal is the product of art, and for this purpose harlequin opals are used. The harlequin opal is simply the matrix of other gems spotted here and there with flakes of color dispersed over an opaque ground, and its name was suggested by the resemblance to the motley tints of the harlequin’s dress. Masses of the matrix, with fragments or specks of opal interspersed in its substance, are soaked for a time in a saccharine solution, and afterwards in diluted sulphuric acid. The porous parts of the matrix absorb a minute quantity of the solution, which is afterwards charred by the sulphuric acid; while the solid and transparent parts remain unchanged and exhibit an increased play of colors upon the black ground.

The ancients undoubtedly obtained their opals from Syria and Arabia or other Eastern countries, for the Hungarian mines which now supply the world with most of the finest gems were not discovered until the fifteenth century. The famous mines are situated on a mountain which is one of the spurs of the Carpathians. They belong to the Seignory Peklin, and are near the village of Czernizka. In the early days of their discovery, and for a long period afterwards, they were explored casually and from time to time. At the present day, however, the explorations are conducted with regularity and the appliances of skilled labor. The surface of the mountain has been removed to a great extent during this long-continued search of many centuries, but as yet no explorations have been attempted into the interior of the ledges. The true matrix appears not to be more than four to eight yards in depth below the alluvial soil. It is arranged in continuous beds of little hardness, but resembling porphyry in color. The opal formation appears to extend to a considerable distance beyond the flanks of the mountain; for, in the cultivated fields below, the laborers often find beautiful gems washed out by violent rain-storms from the exposed and superficial soils.

The opals from these mines are the hardest and most enduring of all the known localities of the earth, yet they have to be carefully tempered to heat and moisture before they can be utilized. M. Frangoll Delius, the Commissioner of the Austrian mines, states that these opals, when first extracted from their rocky beds, are soft, friable, and tender, and not in a condition to be worked. But after they have been exposed to the air and sunlight for some days or a definite time, they become harder, and the stones also become decidedly smaller from contraction. This exposure is required to be carefully regulated lest the stone become fissured by sudden contraction. When exposed to the effects of artificial heat, colors appear sooner than when it is submitted to the action of the sun’s rays. It is curious to watch the gradual unfolding and the display of these beautiful hues. At first the stone is limpid and rayless as pellucid quartz. But as the quarry water is evaporated by the effect of heat or time, and the stone contracts in volume, the iridized reflections then begin to appear, increasing in perfection and variety, until the requisite degree of moisture is expelled. If this evaporation is carried too far by heat the splendors of the gem vanish completely, never to be recalled. It is a singular fact that exposure to the sun’s rays gives the opal much finer hues than the action of artificial heat. And it is also a remarkable circumstance that of all the variety of prismatic hues displayed by this gem, the violet invariably appears the first, according to M. Delius.

The ancients rarely engraved upon the opal, influenced perhaps partly from its enormous value in those times, and partly from its soft and fragile nature. They imitated the gem, however, with such perfection that Pliny declared that it was almost impossible to distinguish the false from the real. Modern gem imitators have utterly failed in producing anything approaching the precious opal in beauty. The assertion of Pliny in regard to the imitation of the glories of this gem has always been received with incredulity by the moderns on account of the failures of our most skilled artisans; but the discoveries among the ancient Phœnician tombs in the island of Cyprus by Di Cesnola rather strengthen Pliny’s remark.

In this collection we may view a great and elegant variety of glass-ware exhumed from the tombs of the Phœnician nobility who lived three thousand years ago or more. Many of these vessels gleam with what appear to be iridescent tints of gold, blue, red, and other colors of the loveliest tints, recalling to mind the most beautiful and gorgeous reflections of the opal. Some of the articles are entirely of one color, while others are composed of patches of various hues resembling enormous opals with broad gleams of pure color. Peligot maintains that these superb colors are clue to the effect of great age; and the substance of the glass being separated into laminæ, the colors may be explained by the law of iridescence. But we are half inclined to believe that they may be due to the skill of the artisan in a great measure,--hence the variety of color in different vessels of the same age. In the famous collection of Signor Castellani there is a solid glass ring quite two inches in diameter taken from the ancient Etruscan tombs. This interesting relic exhibits patches of color as bright as the prismatic gleams, and they do not appear to arise from any disintegration of the material, but rather to be produced by the design of the workman. We surely will not ascribe to effect of age the decided iridescent glaze which we see in the Maiolica pottery of Hispano-Moresque objects of the thirteenth or fifteenth centuries, or in the Gubbio products of the sixteenth century.

The famous opal of history was that which was worn in a ring by the Roman Senator Nonius in the days of the Triumvirate. Its size scarcely exceeded that of a hazel-nut, yet its beauty and perfection were such that it was considered a marvel among the _dilettanti_ of Rome, and valued at the enormous sum of nearly a million dollars. Marc Antony, remembering the sacrifice of the matchless pearl by Cleopatra, and still enslaved by her irresistible charms, sought to obtain the opal, intending it as a present to the siren queen of Egypt. But Nonius refused to part with the treasure which was the idol of his heart, and sought safety in flight. The beauty and charm of the gem may be estimated by the fact that banishment then to a Roman was worse than death. History makes no further mention of this wonderful opal, and even if preserved among the spoils of ancient Byzantium its glories have probably vanished ere this, yielding to the destructive effects of time.

The finest opal of modern times was that which was worn by the Empress Josephine in the days of Imperial splendor. It was indeed a magnificent gem. Its flashing beams of light were so strong and vivid as to give the appearance of living flames of fire, and hence the name of _l’incendie de Troie_,--“the burning of Troy,”--was bestowed upon it. The base of this opal was completely opaque, but the superior portion was perfectly transparent, and through it were reflected a multitude of fiery gleams of red light. The fate of this beautiful gem is unknown. There are two splendid opals still to be seen among the Crown jewels of France, notwithstanding the frequent change of dynasties. One is placed in the centre of the Order of the Toison d’Or, and the other forms the clasp of the royal mantle.

In the imperial cabinet at Vienna is exhibited the grandest specimen of this gem yet discovered. It was found in the mines of Hungary in 1770, and purchased by the Austrian Government. It measures 3³⁄₄ inches in length, and is 2¹⁄₂ inches in thickness. Its weight is about seventeen ounces, and its value is estimated at about $300,000. Although it is injured by several cracks and fissures, it possesses a brilliant play of color, and is justly regarded as the finest specimen known, even surpassing the beautiful fire opal brought home from Mexico by Humboldt, and which is still preserved in the museum at Berlin.

At the close of the last century, but before the Revolution broke out in France, Mons. D’Auguy, a financier of Paris, came in possession of a most remarkable opal of the harlequin variety. It was of oval form, ⁷⁄₈ of an inch in length by ⁵⁄₈ in breadth. This gem was of wondrous beauty, and was pronounced perfect by the connoisseurs. It is now in the hands of the family of Count Waliski. At the same time the well-known amateur Fleury owned a rival to Auguy’s opal, which it exceeded slightly in size.

Another magnificent opal is described by Jackson as having been exhibited at Vienna. It was nearly an inch in length, and was of the harlequin order, having three longitudinal bands from which flashed resplendent flames of light and color. It was pronounced by the virtuosi of Dresden and Vienna to be the third in rank of all the fine opals then known.

In the Musée de Minéralogie of Paris may be seen a splendid opal which has been carved into a bust of Louis XIII. when a child. King very properly exclaims against the barbarism and extravagance where work and material mutually destroy each other’s beauty and value. The Spanish historians, in their marvellous stories of the wonders seen in Mexico at the time of the Conquest, describe the image of the mystic deity Quetzalcoatl (God of the air) on the great pyramid of Cholula, as wearing a mitre waving with plumes of fire, and which was supposed to have been produced by masses of the fire opal.

Dr. Le Conte brought home from his geological surveys in Honduras, a number of beautiful opals from the mines in that country. They have since been cut and mounted in gold with diamond settings, in the form of a necklace, which is regarded by connoisseurs as one of the most valuable jewels in the United States.

At the Centennial Exhibition of the United States, Austria exhibited some very beautiful opals of various kinds, both polished and in the natural state. One of the polished gems was two inches in diameter and valued at $25,000. It was of a faint milky white tint, like most of the Hungarian opals, and displayed a charming arrangement of colors.

The splendors of the opal are best seen when exposed to the direct rays of the sun, and viewed through a magnifying glass of low power. The dazzling scene has no equal in art or nature, for the vivid hues of the solar spectrum are here displayed with the most charming effect. The colors are in broad patches and not blended with their complementary hues as seen in the continuous spectrum, and the effects of the pure green, red, blue, and yellow, flashing forth in perfect purity and intensity, without definite arrangement, remind the observer of the brilliancy of the kaleidoscope. In this fascinating display of hues one might expect to see the colors pass into each other as in the solar spectrum, and as the field of view is changed; but such is not always the result. The red may exhibit a tinge of yellow, or the green a shade of blue before they disappear from view; but generally the patch of color ends abruptly, preserving its purity of tint to the last.

The alternate and irregular flashing of all these varied hues always presents a harmonious spectacle, such is the wondrous power of Nature in all her arrangements and groupings. The stone, when arranged by the art of the lapidary, is almost always cut with a convex surface. However, when the opal is attached to an opaque substance which serves as a reflector to the rays of light, the stone may then have its surface cut almost flat. The colors displayed by this gem embrace quite all of the tints seen in the solar spectrum, and they are as pure. The shades of green, blue, yellow, and red will bear comparison with the hues of the solar spectrum, and the gems of other minerals are rare that can bear this decisive test. Sometimes but one color is visible in the stone, and then it is called emerald or golden opal, according to the tint exhibited.

The purchase of opals in the rough natural state is attended with danger, for often the glittering mass, after being shaped and polished by the lapidary, is transformed into a transparent but hueless stone. The cutting of the opal is always a hazardous operation, from the fragility of the material and the special tact required in determining the shape to be given the gem. We will relate an instance to illustrate the history of the whole.

A traveller from Central America brought home a splendid rough fire opal which dazzled the eye with its fiery reflections. We took it to an honest lapidary, who received it with a doubtful look. The next day the opal was returned, having been shaped into the usual oval form, but only a faint gleam of any of the colored rays flashed from its surface, or the interior. “Is this the gem we gave you yesterday?” we demanded of the artisan. With a smile the lapidary took the transparent stone and roughened its finely polished surface upon the wooden wheel. In an instant the lost fire returned as if directed by magic’s wand. The perfect transparency of the gem, with its high polish, had allowed the rays of light to pass directly through it, and there was but little refraction, but on roughening the surface the light was interrupted and the peculiar property of the mineral displayed. Unfortunately the lesson was not concluded here. At the last touch of the wheel the beautiful gem flew into two parts, and its glories departed in an instant. Saddened with the day’s experience, we took the two fragments, cemented them together, and tossed the stone into a drawer which contained other mineral specimens of no great value. Some months after, while searching for a misplaced mineral, a gleam of light suddenly flashed out as we opened the drawer. It was the neglected and abused opal, which now gleamed with the energy of a living coal of fire. It had recovered its beautiful reflections, and still adorns, notwithstanding its fracture, a most cherished jewel.

Whence this mysterious change? the reader may ask. We can only say that the complete transparency of the stone had been lessened, and perhaps the change was due to the action of some of the ingredients of the cement with which we united the fragments of the broken gem.

Some of the Central American opals have the reputation of fading and becoming translucent and opaque in course of time, or according to the circumstances of exposure. We will relate an instance which forms a part of our experience and education in the study of gems.

A few years ago, two Spaniards arrived in New York with a bag of rough opals brought from Central America, but from what particular locality we never learned. The specimens varied in size from that of a bean to that of an English walnut, and were extremely beautiful. They had a fresh appearance, as though they had been recently extracted from the mines, and many of them had portions of the soft sandy matrix still attached to them. They excited suspicions of not having been properly tempered and hardened by exposure; but their beauty, which reminded one of the perfect glow-worm, or lumps of phosphorus moistened with oil, did not allow the spectator to hesitate about the purchase of them, especially as they were offered at a moderate price. We invested in the purchase of several charming specimens, and never wearied in examining their exquisite effects. Still, we felt a vague suspicion of the enduring qualities of our newly acquired treasures. The most beautiful stone, the size of a small almond, we carried in our pocket for a long time, not only for our gratification but for the purpose of studying the effect of the atmosphere upon its reflections. Soon after our acquisition, we fancied a slight shadow or nebulosity appearing in one end of the stone. We carefully watched it, and before long an indistinct cloudiness began to appear, like the dim and distant haze of a summer sky on the commencement of a storm. Even then we thought it might be mere fancy on our part. But when the shadow changed to opacity, and the transparency of the gem, with its beautiful reflections, vanished, never to return, we were compelled to admit that even substances of the mineral kingdom had their diseases as well as forms of the organic world.

This is indeed but one example to illustrate a theory; but most of those we purchased at that time of the Spaniards have altered in appearance, and some of them quite as seriously. Therefore we have arrived at the conclusion that recently mined opals should be bought with caution; and that the perfection of a rough opal as a gem cannot be safely estimated until after it has been cut by the lapidary.

No definite idea can be given in relation to the price of the opal, so much depends upon the degree of its brilliancy and play of colors. The gem is not sold by weight, but its value is estimated by its size and the perfection of its charms. An opal half an inch in diameter exhibiting fair colors may be worth $5, and another of the same size, of greater perfection, may bring $5,000, or more. The palmy days of the opal were during the period of Roman luxury, as the beauties of the diamond were not then fully revealed, and the opal flashed forth its marvellous beams of color both by daylight and artificial light. The gem then commanded enormous prices. According to the tables of Dureau de la Malle, the opal of Nonius was valued at twenty million sesterces, or about eight hundred thousand dollars. Enormous as this sum of money appears, Catherine of Russia would have given as much for the gem, if its beauty had been in keeping with its reputation.

The commerce of the opal affords a curious example of credulity and superstition, which is in singular contrast with the progressive ideas of our advanced civilization. In times past the changes that sometimes occur in the opal from physical causes have impressed the minds of some excessively superstitious people as due to supernatural causes. And from these trivial fancies the most beautiful and _recherché_ of all that Nature has offered to us in the mineral kingdom has been placed under ban. This superstitious dread may be of ancient origin, and whence its source we know not. But it is a matter of history that the opal was the favorite gem among the Romans in their best periods of intelligence and refinement. So far from being feared at that time, it was eagerly sought for, as it was supposed to possess the power of warning against disaster, and exhibiting the rosy herald of joy. Hence it has been thought that a feeling of superstition as well as of avarice influenced Nonius when his paragon was demanded of him.

It is possible that the dread of the opal may be derived from the superstitious fancies that have descended to us from neolithic times, like the superstitions connected with the ancient stone implements which are now called in Western Europe elf-stones. In Scotland at the present day the ancient arrow-heads of stone are known as elf-bolts or fairy shots, and believed to protect the wearer from disease or misfortune. Thus it appears that stone weapons of an extinct race are used as ridiculous charms by later nations far advanced in civilization. History shows us how elves and fairies were created in the popular imagination from neolithic sources, and how weapons and ornaments of stone, amber, and metal became invested with mystic powers as objects of handicraft of the elves themselves. These objects are not only regarded as fairy charms among the races of the East, but the belief in their powers and use is quite as strong and tenacious among the Celtic portions of Europe. In other countries these primitive ideas of fairies and charms have become modified, and blossomed into poetic fancies to please chiefly the innocence of childhood. Some of these the genius of Shakspeare and other poets have made beautiful, and to these we offer no objection. Poetic license may sometimes invest an object with a positive effect which eventually may assume the appearance of fact. Thus the allusion to changes in the beauty of the opal in connection with misfortune, which was made by Sir Walter Scott, in his novel “Anne of Geierstein,” was taken to heart seriously by many of his readers, and the gem was placed under ban. The popular imagination became so strongly affected that the commerce of the opal in England became very seriously injured; and even at the present day many a timid maiden hesitates over the selection of the opal for ornamentation. Every mineralogist and man of science will rejoice to learn that Queen Victoria exhibits sterling good sense in selecting the opal among her choicest family gifts, thereby presenting a pleasing contrast to the superstitious and foolish fancies of the Empress Eugénie.

To the amateur who loves the rare and beautiful, with a feeling untrammelled by any of the misty traditions of the past or the caprices of fashion of the present, the opal is the dearest of all the gems. For it is not only rare, but it displays the glories of all the other gems; and it is the only one that defies the skill of the modern artisan to imitate. Its flash instantly betrays its character, and places it above suspicion, while quite all of the precious stones regarded as gems are now imitated so perfectly as to require close and careful inspection, and sometimes the application of scientific tests.

When we recall the phenomena of the opal, and the wonders of its reflections, with their strange and sudden disappearance, we may pardon the credulity of the Arabian romance writers in ascribing to the gem supernatural powers. It was a beautiful theory with them that it falls from heaven in the lightning’s flash, and is the veritable Ceraunia. Its charming and mysterious play of colors suggested to their ardent imaginations the glories of Paradise, and hence they invested it with wonderful talismanic properties, and believed it to be the abode of afreets and genii. Alas for romance! Science clearly demonstrates that many of the phenomena which puzzle the superstitious are simply due to atmospheric influences and to the natural laws which regulate the decay of organic and inorganic forms.

THE SAPPHIRE.

“The azure light of sapphire stone
Resembles that celestial throne,
A symbol of each simple heart
That grasps in hope the better part,
Whose life each holy deed combines,
And in the light of virtue shines.”

MARBODEUS.

THE SAPPHIRE.

The colored varieties of sapphire were probably known to primitive man, and were gathered in their rough state to serve as rude ornaments long before the diamond, with its less attractive natural appearance, was recognized as a treasure or a gem. The mountain torrents, laying bare the superficial strata of the gem beds, early exposed to view the sapphires of bright and attractive colors, which readily caught the close, observing eye of the savage; while the diamond, lustreless within its apparent crust, was unnoticed and unknown until civilization became far advanced and revealed the hidden splendors of the gem by the application of art.

We may therefore infer with a reasonable degree of probability that the colored sapphires, though perhaps not the most ancient in mineralogy, were in reality among the earliest gems known to man. The researches of the antiquary and the archæologist rather strengthen this view, for specimens of these stones are found among the ruins of the ancient and long-forgotten cities of Arabia and Persia, while the diamond is not.

This beautiful mineral has been known in the land of its birth from time immemorial as “korund;” and under this harsh name were included all those beautiful gems known to commerce as the Oriental ruby, topaz, emerald, and sapphire. The ancients in the days of Pliny bestowed upon the blue variety the more euphonious name of “hyacinthus.” Modern nomenclature, however, has adopted the term “sapphire” for all the transparent forms of the mineral, reserving the name “corundum” for the opaque and translucent or non-crystallized varieties.

In making use of this word, we have another illustration of the strange adoption of a term which is destitute of any relationship to the characters of the object it is intended to describe. The “sapphirus” of the ancients referred to lapis-lazuli, a blue opaque mineral spotted with minute metallic flakes; and the only significance it bears in connection with any of the forms of corundum is the simple fact that it means azure. If we follow the antiquaries still farther into the mists of early language, in seeking the etymology of the name, we shall probably find even less satisfaction. The nature of this gem, as well as most of the other precious stones, was mere conjecture to the ancients, and they formed their estimate of them chiefly from their hardness and color.

Among the early Greeks, Theophrastus strove in vain to discover some satisfactory basis of arrangement for these minerals, and to explain their forms, their constituents, and the manner of their creation. But his efforts and those of his contemporaries were of little avail; and so Ictinus, when he constructed the marvellous façade of the Parthenon, and Phidias, while he adorned it with immortal statues of marble and other stones, were alike ignorant of the nature of the materials they employed in their work. Several centuries later the treatises of the Latin philosopher Pliny show that science had made but little progress in this respect. The people of India and of the valley of the Euphrates, however, undoubtedly studied at a very early period the internal structure of the precious stones, and the revelations thus obtained had some effect in shaping their religion and their views of civilization.

In searching for the mysterious in the gems, the Assyrians discovered the cuneiform crystals in the interior of transparent sapphires, and adopted the forms for their own use, believing them to be the language of the genii. We have little doubt but that the cuneiform character which now reveals the history of the extinct Oriental empires had its origin from the wonderful crystallizations sometimes seen in the internal structure of the sapphire. These crystals are sometimes visible to the naked eye; but when the polished surface of the mineral is exposed to a magnifying lens of even low power, they appear with startling distinctness, and exhibit forms of perfect arrow-head shape of all colors. The field of vision may at first include but a single arrow-head crystal of perfect symmetrical outline floating in the azure of the stone; but as the field is shifted myriads of crystals may suddenly come into view, presenting a scene of such remarkable beauty and fascination that the observer ceases to wonder at the credulity of Arabian superstition. These crystallizations may occur in sapphires of any hue, and then again we may search in vain for them in many other specimens of the same mineral. Some specimens may contain a very few of these arrow-head forms, while others seem to be composed of multitudes and masses of them. One large red sapphire of four karats weight submitted to our inspection appears to be composed of clouds of these cuneiform crystals; and under the magnifying power of about twenty diameters it presents fields of arrow-heads flashing forth the most brilliant hues, and changing into new scenes of startling and transcendent beauty as the focus is varied. Whatever startled the imagination of the ancients with a new and mysterious beauty was at once invested with supernatural power.

In connection with this theme it is interesting and instructive to trace back the history of the gems and precious stones even within the period of the past two hundred years, and read the descriptions and definitions bestowed upon them by mineralogists. Some of the most gifted of men, like Linnæus and Wallerius, labored diligently to place them correctly in science; but their efforts to define and arrange them properly seem at the present day like schoolboy fancies. Daubenton conceived the brilliant but erroneous idea of arranging them according to their color, taking the solar spectrum for a standard. His idea was to place them in seven genera, according to the seven principal prismatic colors, and constitute species according to the different shades. This able man was not then aware that the sapphire and the tourmaline exhibit quite all of the colors of his seven genera.

Romè de L’Isle was the first mineralogical writer who classed the gems systematically; but it has since appeared that the amateur, Chevalier Baillou, preceded him in his crystallogical ideas; for in 1747 this observer described, in the catalogue of his collection, his views in relation to the properties of gems, and how their characters might be readily ascertained by the tests of hardness and specific gravity, and also by the form of their crystallizations. The distinguished and learned Abbé Haüy became interested and even fascinated with the study of the history and physical properties of the gems and the precious stones; and to his genius we are indebted for much of the information we have at the present day on this subject. He was deeply interested in the nature and characteristics of the Oriental precious stones; and being dissatisfied with the harsh term and the vague synonomy of “korund,” as applied to some of them, he proposed the more elegant name, “telesie.” But science, often disdainful of new terms, finally adopted the name proposed by Wallerius; and at the present time all of the fine and transparent varieties of corundum are called sapphire.

This remarkable mineral is found in mineralogical specimens in China, Siberia, America, and other parts of the world; but all of the fine gems, with perhaps few exceptions, come from Burmah, Pegu, Siam, lower Bengal, and Ceylon.

The island of Ceylon is the most famous of all the localities thus far known, and it is in reality the most wonderful gem deposit in the world. It was known in the period of the Roman Empire, as the land of the luminous carbuncle. This island, which is situated at the southeast extremity of the peninsula of Bengal, and separated from it by a broad but shallow strait, is about as large as England in its area. In the southern centre of the island a group of lofty mountains appears, rising to the height of about 8,000 feet above the level of the sea. On one side this great upheaval descends in successive ranges of hills until the flanks of the mountains subside into the alluvial plains; whilst on the other side the mountain range is characterized by abrupt precipices sometimes of several thousand feet in height. The great gem-producing districts of the island extend along the base of this mountain range for about fifty miles; and the central and richest part is considered to be located around Ratnapoora, which is scarcely two hundred feet above the level of the sea. This want of elevation in the Ceylon gem strata or placers becomes a marked feature when considering the high plateaux in which the diamond occurs in other parts of the world, also coupled with the fact that the two gems are not found together in the same placers. Here are situated the celebrated mines which have yielded vast quantities of the sapphire, especially the blue variety, for an indefinite period of time. They are not small and trivial deposits, but extend over large areas. Some of the plains which cover the deposits are more than thirty miles in extent, and form a large tract of country. Among them are the Kondapalle, Elk, Tolapella, Horton, Bopatalava, Moonstone, Newera Ellia, and many others.

The amount of labor expended in excavations on these plains is stupendous, and evidences still remain which indicate vast operations and remunerative labor in far distant times. The eastern portion of the plain at Newera Ellia furnishes a good example of the extent of the explorations. This region is still called the vale of rubies, and was mined on a grand scale by the ancient kings of Kandy. Many acres of this plain have been completely upturned, and the surface is still indented with numberless pits of large size, varying from three to seventeen feet in depth. The period of these extensive operations is unknown, and is so far distant as to be beyond the mention of history or tradition.

Most of the gem-bearing districts are classed as wild lands, and belong to the English Crown. As yet the authorities have never bestowed a thought upon their value as a source of revenue, and the search for gems is free to the world. Although much territory has been mined in a rude manner in past times, the fields are by no means exhausted, and offer excellent inducements to skilled labor. If some of the energy and determination now exhibited in the South Africa diamond mines could be transported to Ceylon, the gem marts would soon display the splendors of ancient times.

Ratnapoora, which is the gem mart of Ceylon, and situated in the midst of the mines, means literally the city of rubies. The mines adjacent to it and in the district of Saffragan are the principal ones now worked in the island, but the gems are found under the western plains that extend from Adams Peak to the sea. The plains and valleys southeast of Ratnapoora are all gem fields; and the beds of the torrents sometimes contain so great a quantity of broken fragments of sapphire, garnet, zircon, etc., that the sifted sands are used by the lapidaries in polishing gems.

The mining operations are generally carried on by the native Cingalese, who labor in the light of a pastime and only during intervals of their agricultural employments. Some few, however, undertake the labor as a regular business, but they belong to a low and dissipated class, and do not work systematically or with regularity. Therefore, the gem-mining of Ceylon cannot be regarded as a fixed and permanent business.

When an exploration has been determined upon, a small party of villagers set out for the promising region provided with the implements of mining and the means of camping out. The times selected for the operations are after the heavy rains which prevail in June and October, and the floods have subsided. The beds of rivers or smaller streams are often chosen as easier of access than the plains. If the river-bed is selected, the first act of the explorers is to seek for the proper locality where the gem-bearing strata may be found. To ascertain this, the Cingalese thrust a long iron rod of ten or twelve feet in length into the earth, and test the nature of the sub-soil. By means of long practice, the natives can adroitly penetrate the earth to a considerable depth, and, by the resistance to the movement of the rod, can detect the gem deposit of which they are in search.

If the indications are good, the natives proceed to build a hut if they are at a distance from their village, and prepare for the operations, which often extend over many weeks. After diverting a part of the force of the stream so as to form a quiet pool, they proceed to excavate the sand and gravel within a certain area. In order to accomplish this they use hoes with handles fifteen or more feet in length. The top strata are hurriedly raked up and thrown away; but as the pit deepens and the gem stratum is approached, the work is performed with greater care. As soon as the hoes bring up fragments and bowlders of white quartz, or strike a thin ferruginous crust, every particle of the gravel drawn up is carefully preserved. The gravel and sand thus obtained are then placed in large baskets woven of split bamboo and shaped to a conical point at the bottom. The basket thus filled is placed in the current of water, and its contents washed by imparting to it a circular motion. This washing process is kept up until the stones, gravel, and lesser particles are cleansed. During this operation the gems, which are much heavier than common stones, settle at the bottom of the basket, and are there collected together, so that when the superincumbent gravel is removed, the sapphires, garnets, zircons, etc., are easily discovered at the bottom and removed. This is the manner in which the wet diggings are carried on, and is the easiest mode of exploration; but it is by no means as sure or often as profitable as the operations in dry ground on the river banks or in the plains. The dry diggings are much more laborious, as the soil is firmer and the gem strata must be transported to water to be washed and sifted. These dry deposits are found the richest beneath the alluvial plains, which seem to have been in distant times shallow lakes and lagoons.

The gem stratum called mellan is always well defined, and occurs at a certain depth, which seems to correspond to the bottom of the lake at a definite period. This depth varies from two to twenty feet, and is perhaps even greater; but the natives rarely excavate below the depth of twenty feet. This peculiar formation, which is generally horizontal, is composed of a conglomerate of quartz gravel resting upon or mixed with a stiff clay, often indurated by a ferruginous oxide. In among this cascalho, or just below it and adhering to it, are found the fine pebbles and crystals of sapphire, tourmaline, garnet, zircon, spinel, and chrysoberyl. Under these rocks and in peculiar hollows in the plastic clay, which the natives call elephants’ footsteps, the gems are found clustered together heterogeneously, and often so perfect in form as to appear as though created there. At other places they are collected together in these pockets in such a manner as to suggest the idea that they had been washed in by a current of water.

All these varieties of gems, some of them widely differing from each other in composition and form of crystallization, are here embedded together, and seem to have one common origin. This is the true matrix, and the gems are not found in other portions of the soil unless some disturbing force has removed them, like a strong current of water breaking up the cascalho and transporting the gems to alluvions of its own deposit.

It is maintained and generally believed by mineralogists that the sapphire is formed in crystalline rocks; that in process of time the matrix is disintegrated, the gems set free, and washed down to the alluvial soils where they are now found. It is also thought that the gem-seekers might with patient care trace the precious stones to their source in the primitive ledges or the mountains, as the gold miner often follows for long distances the particles of gold in the soil until he discovers the parent vein in the solid ledge. But in Ceylon this view is not entertained by the natives; and all scientific efforts to find the sapphires in the mountain ledges have utterly failed. All trace of the sapphire and its attendant gems ceases as soon as we reach the limit of the gem stratum, and what seems to have once formed the shore of the lagoon. Beyond this plainly marked outline we may search in vain for the least sign of a connection with the older rocks either adjoining or at a distance. The result is the same if we examine the ledges on the same level or those of a higher elevation.

In some countries, in the granular limestone of New Jersey for instance, or the ripidolite of North Carolina, the granite of Siberia, or the dolomites of Switzerland, we find sapphire, or more properly corundum, of undecided colors, of inferior transparency or even of opacity; but it is very rare that a specimen is found of sufficient purity for ornamentation. The most transparent and perfect of these sapphires are generally impaired by cleavage planes which traverse the stone in several directions, preventing refraction of light, and often so marked as to appear like flaws. This circumstance indicates that the forces that deposited corundum and the fine sapphires were certainly different in character, or that the conditions in which they were exerted were not the same. For in Burmah, Pegu, India, or Ceylon, and wherever the perfect sapphires are found, they have one common matrix, and that is the peculiar ferruginous conglomerate.

This conglomerate is recognized as a recent formation; and how came these gems, which are believed to be as old as creation itself, to be found among it? This formation is not only recent, but it is actually taking place all over the world at the present day, and examples may be found in almost every country. We find in many places the peculiar strata of sand, gravel, and masses of stone in proper position to change into conglomerate, which requires the action of water highly charged with iron and lime or silica. Darwin found these stony layers in process of forming on the beaches of the Cape de Verde Islands, and in vain attempted to knock out a bolt of iron which had been cast ashore from some wreck not long before, and had in a short space of time become firmly fixed in the conglomerate. We may observe the same process taking place to-day on the coast of Cornwall, and among the _débris_ of the ledges of the Abrolhos Islands. In dredging rivers large masses of solid conglomerate are often brought to light. The Thames has furnished many examples; and not many years ago a cannon-ball embedded in a crystalline calcareous rock was taken from the bed of the Mediterranean not far from the mouth of the Rhone. Fresh water laden with _débris_ of vegetable matter also possesses the same cementing action as sea water, and an excellent example is seen in the allios now forming in the Landes of southern France. This allios is also a conglomerate, which has formed and is now forming at the depth of about three feet below the surface. Here the conglomerate of sand, pebbles, and angular fragments of rock is firmly cemented together by the rain-water, which filters down from the surface of the earth laden with vegetable matter. The cascalho in which the diamond is found is of similar character, and has a similar origin, for we likewise find there traces of vegetable _débris_, and the diamond itself contains germs of fungi and vegetable fibres of higher organizations.

But whence come the elements which form the gems? the inquirer will say. Can we gather figs from thistles? Marco Polo in the thirteenth century visited these gem beds, and has left his views in the following lines: “In ista insula nascuntur boni et nobiles rubini et non nascuntur in aliquo loco plus. Et hic nascuntur safri et topazii, amethisti et aliquæ aliæ petræ pretiosæ et rex istius insulæ habet pulchriorem rubinum de mundo.” Buffon, four centuries later, in seeking for the causes of the formation of this mineral, observed the peculiarities of the matrix on this island, and boldly stated that the origin of the precious stones like the rubies, the sapphires, and topazes of the East is the same as that of the diamond. He also stoutly maintained that these stones form and are found in the conglomerate in which is collected the _débris_ of other matters. The researches of Sir Samuel Baker and others on these deposits seem to indicate, if they do not prove, that the sapphire in particular was formed in the sands, clay, or conglomerate where it is now found, and was not set free by the disintegration of the old crystalline rocks. Nordenskiold recognized these gem beds as true placers, but was inclined to think the gem strata had decayed and left the gems free. An article published some years ago in “Once a Week,” and supposed to have been from the pen of Sir Samuel Baker, who had lived many years at Ratnapoora, and had attentively examined the gem-bearing formations, gave the following account:--

“A common but erroneous belief is that the gems are formed in the mountains and washed down by the abrasion of the rocks and deposited in the alluvial bottoms. If it were so, they would have been traced to their source and sought for in the mountains, where they would naturally be found in greater quantities; but the natives never think of searching for precious stones in such places, and in the localities where they are found there does not appear to have been any local alteration in the veins of gravel since they were first thrown there; and my own conviction formed from observation on the spot, and for this and other reasons following, is that the sapphire and other gems have been formed and are still forming in the places where they are now found. In the first place, rounded sapphires and sapphire crystals with facets of brilliant lustre are found lying side by side. Secondly, both the rounded stones and the numerous perfect crystals, with their pyramids unbroken, show that they were never broken from other rocks, but were formed unattached to any matrix, in a soft medium such as fine sand or clay. I have seen hundreds of these taken loose from the same spot. Thirdly, crystals of sapphire are found with their edges reduced, yet with brilliant facets, which is inconsistent with their reduction by rolling. Fourthly, sapphire being much harder than any other stone with which it could come in contact, it is not easy to understand how any attrition could be brought to bear upon it to bring it to the beautifully translucent polish which the rounded stones usually bear more especially considering the short distance from the mountains to the alluvial bottoms between which the water-wearing process is supposed to be effected.

“It is remarkable that the rounded sapphires and rubies are always the densest and of the finest water and color; showing that they were formed by different chemical forces from the others. In short, there is no more reason for supposing rounded sapphires to be water-worn than for supposing that the bowlders of jasper, for instance, on the Egyptian desert were so formed, when a fracture shows them to have been formed in concentric layers and to be in their original state. The same remarks apply to the crystals of some other minerals, as zircon, tourmaline, and spinel.”

The mineralogist, in contesting this opinion, will point to the round pebbles of sapphire as evidence of disintegration and subsequent aqueous action. But upon careful inquiry we shall find that these nodular masses are regular concretions and natural formations, which do not owe their form to the abrasion of exterior force, but are the results of crystalline action. We shall also find that these peculiar stones always form the finest specimens of the class of gems to which they belong, whether sapphire, diamond, tourmaline, topaz, or chrysoberyl.

In regard to beauty of color, density, hardness of texture, and brilliancy, these apparently water-worn masses are decidedly superior to the perfectly shaped crystals, and among all the true gem mines of the world this rule is observed. In the conglomerate of Ceylon we often find gems whose appearance indicates the shock and abrasion of waves or currents of water, while we find in adjoining places perfectly formed crystals whose facets display a lustre as brilliant as on the day of their creation. Some, then, have perhaps been moved about by aqueous action, while others have never stirred from their first position.

Among all the multitudes of sapphires taken from the mines of Ceylon, we have never seen or heard of a specimen fairly attached to any rock as a matrix. Sometimes the ferruginous cement which is one of the necessary components of the matrix unites accidentally the rough gem to a mass of quartz, but all the sapphires we have seen exhibit no sign of having been attached permanently to any mineral substance. In fact, all the rounded stones and the more perfect crystallized specimens have the appearance of having been formed in a soft medium like sand or clay.