Leisure hours among the gems

by Augustus C. Hamlin

Artificial gems, rivalling in beauty of color the most brilliant and delicately tinted of the productions of Nature, are now made at Paris and in other European cities. The establishments at Septmoncel in the Jura alone employed a thousand persons, and fabulous quantities of the glittering pastes were made there and sent to all parts of the world.

A fine specimen of prase, when cut, affords a fair imitation of the emerald. The green fluor-spar which Haüy called “emeraude de Carthagène” may also be substituted, but the application of the file detects the trick with ease. Some of the green tourmalines approach the emeralds in hue very closely, and by artificial light it is impossible to distinguish them from each other. Fragments of quartz may be stained by being steeped in green-colored tinctures. The Greeks stained quartz so like the real gem, that Pliny exclaimed against the fraud, while declining to tell how it was done. The Ancona rubies at the present day are made by plunging quartz into a hot tincture of cochineal, which penetrates the minute fissures of the rock.

But notwithstanding the high art reached by modern glass-makers, they are yet far behind the ancients in imitating the emerald in point of hardness and lustre. Many emerald pastes of Roman times still extant are with difficulty distinguished from the real gem, so much harder and more lustrous are they than modern glass. The ancient Phœnician remains found in the island of Sardinia by Cavalier Cara, in 1856, show fine color in their enamels and glass-works. The green pigment brought home from the ruins of Thebes by Mr. Wilkinson, was shown by Dr. Ure to consist of blue glass in powder, with yellow ochre and colorless glass. From Greek inscriptions dating from the period of the Peloponnesian war, we learn that there were signets of colored glass among the gems in the treasury of the Parthenon.

Of all the emerald imitations that have descended to us from antiquity, none are more remarkable, none more interesting to the antiquary and historian, than the famous Sacro Catino of the cathedral of Genoa. This celebrated relic is a glass dish, or patera, fourteen inches in width, five inches in depth, and of the richest transparent green color, though disfigured by several flaws. It was bestowed upon the Republic of Genoa by the Crusaders, after the capture of Cæsarea in 1101, and was regarded as an equivalent for a large sum of money due from the Christian army. It was traditionally believed to have been presented to King Solomon by the Queen of Sheba, and afterward preserved in the Temple; and some accounts relate that it was used by Christ at the institution of the Lord’s supper. The Genoese received it with so much veneration and faith, that twelve nobles were appointed to guard it, and it was exhibited but once a year, when a priest held it up in his hand to the view of the passing throng. The State, in 1319, in a time of pressing need, pawned the holy relic for 1,200 marks of gold ($200,000), and redeemed it with a promptness which proved its belief in the reality of the material, as well as in its sanctity. And it is also related that the Jews, during a period of fifty years, lent the Republic 4,000,000 francs, holding the sacred relic as a pledge of security. Seven hundred years passed away, when Napoleon came; and as he swept down over Italy, gathering her art treasures, he ordered the “Holy Grail” to be conveyed to Paris. It was deposited in the Cabinet of Antiquities in the Imperial Library, and the mineralogists quickly discovered it to be glass. It is due to the memory of Condamine to state that he was the first to doubt the material of the Sacro Catino; for, when examining it by lamplight in 1757, in the presence of the Princes Corsini, he observed none of the cracks, clouds, and specks common to emeralds, but detected little bubbles of air. In 1815, the Allies ordered its return to the cathedral of Genoa. During this journey the beautiful relic was broken; but its fragments were restored by a skilful artisan, and it is now supported upon a tripod, the fragments being held together by a band of gold filigree. This remarkable object of antiquity, which is of extraordinary beauty of material and workmanship, furnishes a theme over which the antiquaries love to muse and wrangle.

Another of the antique monster emeralds, weighing twenty-nine pounds, was presented to the abbey of Reichenau, near Constance, by Charlemagne. Beckman has also detected this precious relic to be glass. And probably the great emerald of two pounds weight brought home from the Holy Land by one of the dukes of Austria, and now deposited in the collection at Vienna, is of the same material. Another, more than eight inches long, was preserved in the chapel of St. Wenceslaus at Prague. The hardness of our glass is yet far inferior to that of the ancients; and even the ruby lustre of the potters of Umbria, which was so precious to the dilettanti of the Cinque Cento period, has not been recovered.

The enormous emerald dishes and statues and obelisks described by Herodotus, Theophrastus, Appian, and others were undoubtedly constructed of glass, and exhibited to the ignorant multitudes as formed of monster emeralds.

One of the most curious of these impositions was the sculptured lion on the tomb of Hermias on the island of Cyprus, which had emerald eyes which shone so brightly as to frighten away the fish in the sea near by.

The wonderful “Table of Solomon” which formed a part of Alaric’s Roman spoils, and was taken by his Goths to Spain, where it was captured by the Arab invaders and afterwards sent to Damascus, was probably another specimen of the ingenuity of the glass-workers of Alexandria or Tyre. It is described by one of the Arabian historians as of a marvellous beauty, being formed of a single slab of solid emerald, encircled with rows of pearls, and supported on many feet composed of gems and gold.

The famous Barberini vase, found in one of the tombs of the Roman emperors, and exhibiting white figures upon a dark-blue ground, was long thought to be carved from some variety of sardonyx, but proved in modern times to be of hard antique glass. Of similar material the unique ewer in the Brescian Museum and the vases in the Palace Borbonico are composed, and all of these are of great antiquity. The sapphire cup of Theolinda, the once celebrated Queen of Lombardy, now preserved in the Cathedral at Monza, is glass.

There are but very few stones whose colors resemble that of the emerald, and therefore frauds are easily detected. A well-selected specimen of prase may be passed as an inferior emerald, as well as the translucent stones cut from the Chinese jade; but their want of transparency offers a serious objection to them as a gem. The green tourmaline, when it approaches the emerald in hue, is of equal value. The green zircon and the green spinel would be far superior to the emerald in brilliancy, and therefore of greater value to the amateur. The chrome-green garnet of Hungary and the emerald-green garnet of Siberia would command a high price, if of pure color, as they surpass the glucina emerald in eclat and are moreover exceedingly rare. The peridot may assume the exact hue of the Granada emerald. The glass imitations are almost fac-similes in hue, and are far superior in brilliancy to the mineral itself; but their softness, which readily yields to the file, betrays their nature without difficulty.