COLOR is one of the most important qualities of the diamond. Generally, fine color means the absence of color, or a pure, clean, colorless transparency. As tints appear in it, the stone is called off-color, which means that the color is not good. Tints of pink and blue, however, are considered extra fine. So also fine color sometimes means a rich or rare color as the term is usually applied, as pink, green, blue, yellow, etc., for the diamond occurs in these and other colors in various tints and shades.
Color in diamonds is the opportunity of many dealers, and the despair of others, for it is very deceptive, and the public is so confident about what it thinks it sees. What it really does see is not always inherent, but is reflected into the stone from the gold in which it is set, or by conditions of the light under which it is seen.
Usually the diamond is white with a tint of yellow, brown, or green. The yellow-tinted are by far the most common, the brown are abundant, but the green are comparatively few and come mostly from one district, i. e., Bahia in Brazil. Absolutely colorless, or white stones, are rare ; so also are those having a bluish tint. All these are included in the general term ” white,” to distinguish them from the ” fancies,” which are stones of such decided depth of color as to make them desirable on that account.
Diamonds not distinguished by a color prefix are graded and quoted by dealers as follows :
” Jagers ” are white stones with a bluish tint. They are popularly supposed to be from the Jagersfontein mine of the Orange River Colony in South Africa, as many of the stones from this mine are of that character, but all diamonds of similar quality except ” Rivers,” after they leave the cutter, are now included under the name.
Next to these and preferred by many are the ” Rivers.” These are white stones of extreme purity And extraordinary hardness, found in river beds. The brilliancy is peculiarly sharp and the color by comparison with other, white stones reminds one of snow. The perfection of these qualities distinguish stones taken from wet diggings, and though all ” Rivers ” have not the color requisite for this classification and some have a bluish tint like the Jagers, it is generally conceded that they are all harder and therefore more brilliant than those from dry diggings. The fine white stones of Brazil and India, unless old-cut, are now included under this head. Old-cut stones of this character are termed ” Old Mine.”
The next grade is called Wesselton, after a mine in South Africa of that name. The color is very nearly equal to the Rivers, though it lacks somewhat of the purity and snow-whiteness of the latter and the brilliancy is not quite as sharp.
Crystals,” which are subdivided into ” top crystals ” and ” crystals,” are white stones showing a trace of yellow when compared with the higher grades. These are the white stones of the high-class jewelers. Diamonds of the color known to the general public as white, are called in the trade, “silver capes.” They also are graded as ” silver capes ” and ” top silver capes.” ” Capes,” also subdivided in the same way, are tinted still deeper and are sold to the public often as ” commercial white.” By-water” are quite yellow, though the color is not deep enough to place them among the fancies, and is sufficiently lost to the eye when mounted to warrant their retention in the list of white stones.
Browns are all included under the one classification. Those having an almost imperceptible shade of brown are separated and sold as steel-white, pink, etc. Fancy browns are not included in this grade.
The green-tinted diamonds, being little known by the public and many dealers, are used by manufacturers and sold when mounted, as white. As those who look for color have only yellow in mind, the greenish hue is seldom detected, especially as stones of this character rarely weigh much over / carat and are usually smaller. A few are of sufficiently deep color to be classed as fancies. They are a light apple-green similar to the Willemite.
In the list of fancies which have been found, are the following, given in the order of their rarity, the first being most rare. Emerald green, red, sapphire blue (invariably of poor color), pink (seldom more than a tint), black, orange, canary, coffee-brown, reddish-brown, golden-brown, and tints of violet and blue which are the more rare as they become deeper.
There is another class of stones the color of which varies materially according to the light in which they are viewed. These are classified as ” false colors.” As the new Premier mine of South Africa produces many of this character, they are now becoming known as ” Premiers.” Generally they are more or less cloudy or milky, with a bluish tint which changes in some lights to a yellowish or brownish shade. They are very deceptive, and are often sold under favorable conditions for better than they are. Many dealers as well as the public are deceived by them.
These are the classifications which have grown out of the close methods of the London Diamond Syndicate, but notwithstanding the sharp lines of difference which have been drawn, in the determination to extract the last penny from the public for every item of quality, there yet remain differences of tint, and quality of color, in individual stones, sufficient to puzzle the judgment even of the dealer, and it is often found difficult to match perfectly a pair of stones from a parcel, closely graded as they are. There is reason too for the fact that experts sometimes differ in their judgment when comparing two particular stones.
To understand the condition, it should be remembered that color is not a thing of itself or an exact quantity or quality of a thing, but an optical phenomenon. It is a sensation conveyed through the eye to the brain by vibrations or waves of certain lengths and rapidities of motion, which in the transmission become to us what we know as color, some waves producing the sensation of one color, some another, as sound varies to the ear in the notes of an octave. The white light of the sun is the sum of these variations. This white light may be decomposed, and the constituent rays shown in the spectroscope, as the primary colors from red to violet, together with others which result, in their effect upon the eye, from modifications by combination with each other. These colors appear in the spectroscope to the eye, in horizontal bands of variable width according to the media through which the light passes, as violet, indigo, blue, green, yellow, orange and red. Now the different elements of the various objects we see, when white light falls upon them, absorb some of its constituent rays and return some to the eye separated from the others, thereby producing the various sensations of color. There are several reasons, however, why persons differ in their judgment of them. Practically every stone has qualities which would produce a definite degree of color to the eye under the same conditions. But exactly the same conditions always are almost impossible, for the variation of position when the stones are placed side by side is sometimes sufficient to affect the light vibrations and therefore the color appearance to the eye, in favor of one of them.
Again, the eyes which see, vary. A ray of pure white light passed through a prism divides, on the screen, into the spectroscopic bands, which merge one into the other in a definite unvarying gradation, but no two persons would draw the dividing lines between them in the same places. One sees more yellow and less green and the others vice versa. Beyond this, it is being found that many people are absolutely blind to some colors. There is of course a normal average perception, but many are not up to that average, and of those above it, few have trained the faculty, under the distractions of a broken surface of sharply reflective and refractive material, sufficiently to see clearly the exact color of it. The sensation of the yellow ray which reaches the brains of some, could not be conducted by the optic nerve of ‘others.
Experts are slow to pass judgment on the high grades of diamonds in a poor light or unfamiliar surroundings and for one to say positively that the color of a very fine stone, is better or poorer than that of a similar one, without comparison, is rash, and good evidence that he is not familiar with that kind of material. One’s physical condition also influences the perception of color. Experience teaches many dealers that there are days when they are not in good condition to buy diamonds. There are few but wonder at times, as they become bet-ter acquainted with their purchases, how they could have paid as much as they did for certain lots.
Surrounding buildings, the color of the walls and ceilings of a room, association, the kind of mounting it is in, all affect the apparent color of a diamond. Jewelers frequently hurt their diamond trade by papering the walls and ceilings of their stores with yellow, brown, or crushed strawberry, for which many seem to have a predilection, or are damaged by a neighbor across the street painting the front of his building with some vivid tint. The light is thereby tainted and the adulteration is reflected in the diamond.
The quality of the light under which a stone is viewed has much to do with the apparent color. A cloudy day will darken the color of some and neutralize that of others. Dealers sometimes take advantage of such conditions; they are frequently embarrassed and lose sales by them. The best light in which to judge fine shades of color is an unimpeded north light.
It will be understood by the foregoing that for a person who has not had sufficient experience to instinctively estimate and balance the various influences by which he may be surrounded, it is quite difficult to grade a stone at sight.
Looking intently or for a considerable period at some decided color just prior to locking at a diamond, will influence the judgment. Some effect of the accidental or complementary color thereby produced, undoubtedly remains, and becoming mixed with the new impression, produces a sensation of color which is not true to the last thing brought under observation. For instance, if one, after working for some time over a paper of emeralds, were suddenly called upon to judge a fine white diamond, he would probably see a tinge of brown in it. The brown would not be in the stone; it would be a left-over impression, or the ocular spectra produced by gazing at the green emeralds. In a like manner amethysts or blue sapphires would prejudice against white stones by creating an impression of yellow. On the other hand, the blue of a bluish white stone would be intensified to a purplish or violet tint by first fixing the eye for a short time upon yellow sapphires or topaz, or a canary diamond. The off-hand adverse criticism by a buyer, or the buyer’s adviser, of a stone which is really white, often tempts the dealer to allow his customer to deceive himself and sometimes obliges him to sell a poorer stone at a higher price than that he would have preferred to sell.
Color is often unequally distributed through the stone, or the elements which cause the sensation of color are so placed that position modifies it. There are stones which show more color when viewed from the back than when faced up to the eye. In others it appears deeper when viewed edgewise than in any other direction. Occasionally the poorest color appears in the face of the stone, but this is seldom the case, as cutters and cleavers naturally try to arrange their work so that the best will come to the front in the finished product.
The cutting of a stone has its influence on the apparent color. One that is cut shallow will not appear to have as much as it really has. A thickly cut stone makes it more perceptible. If the body of a stone is white and the culet is cut in a bit of color, that will appear throughout the stone when it is faced up. Oriental cutters take advantage of this in the cutting of rubies and sapphires especially, by placing the culet in a stratum of good color, even if they must spoil the shape of the stone to do so. Diamonds are not affected thus to the same degree, because they seldom have strata of decided color and when they do, the tints are so weak that the differences are not easily distinguished, though the result is noticeable as an uncertain color which varies with the changes of light and position in which it is seen. These are the false color stones. Most of them appear blue with a tendency to violet under a strong natural light, the tint becoming stronger and therefore better as the stone approaches the eye. Usually the blue shows to best advantage under a loup with an inch focus, though one experienced, by moving the stone to different angles, will catch fugitive glimpses of the deteriorating hues included. These are generally yellow, sometimes brown. Upon removing these stones from the clear sunlight to a mixed or artificial light, the inferior colors become dominant.
There is another item of importance, though it escapes general observation. It is the quality of color. In fancies, the hues being deep, it is more noticeable and therefore regarded. A fine canary is of a clean bright yellow like the feathers of the bird after which it is named. Frequently the yellow is tainted by a greenish cast; many have a dark, murky quality, and are really very deep by-waters. Inferior browns are of an ashen or blackish character. Of the other colors in which the diamond occurs, greens and orange are generally good, as the apple-green, if less rare and desirable than the emerald-green, is nevertheless very beautiful, and orange is always so. Absinthe-green diamonds are some-times very pleasing, though stones of this color are apt to have an oily appearance like some zircons, in which case the center is dark. Occasionally these show wide variations of color under different lights; one in New York being absinthe-green, golden, brown, and red, ac-cording to the light in which it is seen. In red, the diamond never approaches the magnificence of the ruby, and in sapphire blue it is seldom equal to a good Ceylon sapphire even. The famous Hope diamond would be considered quite inferior as a sapphire.
In the variously tinted white stones, and the untinted white, quality of color is more elusive. The white will be found by comparison to be blackish, steely, or snowy. The latter is characteristic of river stones, especially the Indian when they are white, and is in the opinion of some, the superior of all, because it is the cleanest and purest. There is something intensely fascinating about one of these pure white stones, and it is worthy of remark, that members of families which have for generations owned fine gems, if they are interested in precious stones, instinctively prefer them. They are al-most invariably the choice of persons to ” the manner born.” Most of the white stones marketed are of the steel white variety, and they are finer than the blackish, which are few and undesirable.
The quality of yellow-white stones varies from a clean bright yellow to a dark and somewhat muddy shade, in gradations so fine that only an experienced eye can detect them by comparison. The more clean the yellow of the tint, the better it is. Brown-white range from ashen to red-brown and are all undesirable, as they look dark when mounted.
It should be remembered that in writing of quality of color no reference is made to its depth, but its character only. In a general way the quality of color is better, as in fancies, when it is clean and bright, and poorer as it becomes dark or muddy.
Color is affected by the mounting in which the diamond is set. Usually platinum neutralizes yellow tints to some extent, and is helpful to most white diamonds. To some, however, it imparts a leaden appearance. Polished gold is more apt to give an appearance of color to a white stone than the dull yellow of roman gold. Nothing marks more the individuality which diamonds possess than a study of them in different mountings. They will appear smaller or larger, whiter or more off-color, brilliant or leaden, according to the mounting in which they are placed. As an illustration of this fact, the writer remembers a sample ring made by a manufacturer of mountings some years ago. It was a peculiar style and was universally decried by the trade. As he could not sell it and it was odd a merit to him he put a diamond in it and wore the ring him-self. Immediately the diamond was admired and sold. the buyer stipulating only that he would not buy the setting. Another was put in its place and at once met with the same fate. He repeated this until the ring could not be used further, and the dealers upon whom he called had all become familiar with the ring and probably with its salesmanship. A diamond in it looked whiter, larger, and more brilliant than it did out of it, though the manufacturer found in his experiments that occasionally a stone would not appear to good advantage in it. Great care should be exercised in the choice of a setting for a diamond, especially if it is a very fine stone. Many fine gems are made to appear mediocre by the whims of inexperience, or the ignorance of an in-artistic jeweler.
There have been many attempts to improve or change the color of diamonds. If one remembers that color in a one carat stone may make a difference of several thousand dollars in the price of it, one will realize the incentive. At this writing a blue-white stone weighing one and one quarter carats is held by the importer at twenty-five hundred dollars; a perfect brilliant by-water of the same size can be bought for one hundred and twenty-five dollars.
In old times some charlatan periodically claimed the ability to remove the coloring matter from diamonds. Some men of reputation made the same claim, among them one who styled himself the ” Inventor of the process for the decoloration of diamond rough.” The result was said to be accomplished by heat and chemicals.
De Boot asserted that Rudolf II could take not only color, but flaws from diamonds. If the statement was true, the secret died with him. It has been stated of late that the emanations of radium permanently improve the color of diamonds, changing the yellow to a bluish tint, but time for proof is yet wanting, and the cost and scarcity of radium debars thorough investigation at present. That radium has a great influence on some diamonds has been demonstrated. Under its influence some stones will become brilliantly phosphorescent, and the color of the light varies with different stones. Two large diamonds, one blue, the other black, as the radium was brought near them, glowed brilliantly, retaining the light for some little time after they were removed from the influence of the radium, the black stone holding the light somewhat longer than the blue. This was re-versed when the stones were subjected to the ultra violet ray, as the black stone showed a red light for 15 seconds and the blue stone shed light for five seconds after the black stone had lost its brilliancy. Actual contact of the two substances is not necessary to produce the result, as a mixture of radium and willemite held ten inches under the board on which the diamonds lay, caused them to glow in the same manner. Willemite, a zinc silicate, it was found, in combination greatly increased the power of the radium.
Some twenty years ago it was discovered that dishonest persons were ” painting ” diamonds. This was done by applying a purple dye or ink to the under side of the stone on and around the culet. When dry this was rubbed down until the paint became imperceptible to the casual glance, but leaving enough on withal to neutralize the yellow of the stone, or if the diamond was white, to give a bluish tint to it when faced up. Not only was this done with individual stones, but importers found that some of the dealers in Europe from whom they bought parcels of diamonds, were open to suspicion. At one time there was considerable and general alarm. Importers and dealers everywhere resorted to the alcohol and acid bottles and there was a great cleaning of diamonds. Importers found they had paid more for some stones in Europe than their customers were selling the like for here. The bargains of bargain buyers disappeared. Pawnbrokers discovered that they had loaned more than the market value on some of their pledges.
Before suspicion was aroused there were men who habitually bought off-color stones in rings and after painting, pawned them at a profit. For some time a reputable manufacturer painted yellow diamonds and mounted them for his customers with the paint on, in closed English set rings. When he found that the device was being used to deceive patrons instead of improving the appearance of stones sold for what they really were, he discontinued the practice.
The fraud did not last long, as the trade soon became too watchful, and those who offered such stones acquired at once a reputation which deterred knaves and caused honest men to watch closely all stones which passed through their hands. A painted stone is rarely seen now.
If well done it is difficult to find evidence of the paint with the naked eye, but on turning the collet side about at different angles, a metallic iridescence on the facets will often betray it. When in doubt, the safest plan is to wash the stone thoroughly in alcohol.
Another fraud has succeeded the painted diamond. Many diamond doublets have been made and sold lately. This is not a new thing but an old imposition revived. They are made of diamond from the table to the girdle and joined there by invisible cement to a collet side of white topaz, but they are not good. The topaz back fails to give the proper reflections and the stones look dead.
These practices are very old, and become epidemic as they are forgotten, or a new generation of unwary buyers succeed those who have had experience.
Price is not always indicative of beautiful color. Sometimes it corresponds with the rarity of the stone only. A black diamond is odd, unique, rare, but not beautiful, yet it will bring a larger price than others of exquisite color. This is true also of some oily absinthe greens, cloudy blues and sapphire blues. Many of the pinks which command very high figures, look weak and washed out when compared with a fine golden brown of half the cost. Frequently the blue-white stones appear dark and less attractive when placed side by side with the snow white gems of India or Brazil. Absolutely pure white diamonds are probably more scarce in the market to-day than blue white, yet the latter bring a higher price because the public has been educated to regard them as the finest of all. This education was made when they were also more rare than white. It is true that a blue-white stone will make any but a snow-white appear off-color by comparison, but the snow-white has a quality which makes even the bluish tint look off-color. The term, ” off-color,” means that the ideal purity of the stone is destroyed by a taint of color. As generally applied, it means by a tinge of yellow or brown. As popularly understood, it refers to yellow only.
To judge the color of a diamond, endeavor to get an unobstructed light, a north light if possible. Do not hold it in the fingers, but by diamond tweezers, or in the crease of a diamond paper, as to put the breath on it properly, it must be cold. Then breathe quickly with a slight puff upon the face of it. This casts a mist on the stone for a second or two, and enables one to see the front color without the confusion which arises from its reflective and dispersive powers. Having noted this, turn the stone in the paper edge-wise to the eye, and partially close the paper over it to ward off outside influences. The body color of the stone can then be seen. If it is a blue-white stone, try it in various positions and lights and under a loup, watching closely all parts of the stone for a tinge of color other than blue. If there, it will be seen at some angle and will be prominent in some light. If found, the color is false.
Under artificial light, diamonds with a tinge of brown appear dark ; yellow is much less perceptible than by daylight ; gem canaries even cannot then be distinguished from ordinary stones. Some fancy mixed color stones become strangely transformed. There are specimens, green to gold in daylight, which change to brown and red by artificial lights. Under an arc light, some blue stones lose color, and others not so blue assume a deep violet hue, very beautiful.
Other things being equal the relative market values of color in the diamond are about as follows:
Fancies : Emerald-green, red, sapphire-blue, pink, orange, tints of violet-blue and blue, canary, black, and brown.
In what are termed white stones : Blue, snow-white rivers, jagers, wesseltons, crystals, silver-capes, very light brown, very light green, capes, yellow (by-waters) ac-cording to depth of tint, and browns.
The flaws which occur in the diamond consist mainly of so-called carbon spots, and fissures or ” glasses ” (glessen) as they are sometimes termed in the trade. There are comparatively few stones which are absolutely flawless, though many of the faults are almost imperceptible to the naked eye and are of such a character that they do not hurt the brilliancy or beauty of the stone. Formerly, absolute perfection was not demanded to the same extent as now. Then, diamonds were used almost entirely by a class of wealth and leisure in whom the keen trading instinct was not developed. Accustomed to jewels, if one pleased the eye, they did not enter into a close inquisition of details. This class appreciated observable qualities. If the ruby was a fine red, the sapphire a beautiful blue, and the deep rich green of the grass distinguished the emerald, offered to them, they did not stop to consider the effect of flaws upon a possible sale later. So also with the diamond. If it was brilliant and the color was good, that sufficed. But as people unaccustomed to diamonds became large purchasers, the trading instinct of generations manifested itself. These in buying, never lost sight of market value and anything which might affect it. They could not reach in a lifetime or a generation or two, the care-less prodigality which bought with no regard whatever to turning the jewel into cash again. The diamond was to them more an article of merchandise than a jewel. Every detail which might hinder a ready sale, was noted, either to be avoided, or used as an argument to whittle down the cost. Not educated by familiarity to the more subtle shades of life and color, their criticisms fell upon the one thing they could detect, the flaw. As with a man of noble parts his one fault will be decried by those who fail to appreciate the otherwise divine beauty of his character, so the new buyers of diamonds refused many a noble stone because of flaws which could not hide nor mar the magnificence of worth and beauty. And this general condition was fostered by the many new dealers. When a jeweler first adds diamonds to his stock, his one demand is, perfection; his one claim when he offers them for sale, perfection. He learns the value of other qualities later.
This critical demand for perfection grew rapidly when the people of the United States began to buy diamonds. Jewels to many of them and their forebears had existed only in their dreams of romance and royalty on the other side of an impassable barrier. When these persons awoke to the fact that fortune had enabled them at will to possess these old-time splendors of their dreams, they brought to the buying a hypercritical taste which knew little beyond flaws. Nor could they as a class be deceived in a matter to which they had given attention, for the people of the United States are both sharp and inquisitive. They soon learned to back their demand for perfection with the ability to discover for themselves any imperfection, and today it is common for a would-be purchaser, to subject the diamond he has under consideration to careful inspection through a jeweler’s loup or magnifying eyeglass.
This general insistence on perfection finally affected the better educated class of buyers, so that they also demanded freedom from flaws in addition to the positive qualities of color and life. The tremendous demand for diamonds in the United States developed in the last decade, coupled with the control of the world’s supply held by the Anglo-African Diamond Syndicate, has finally enabled that powerful corporation to check this unreasonable demand for absolute perfection. The Syndicate has of late forced upon the American public, imperfect stones, not only by marking the price of perfect stones much higher relatively, but also by reducing the proportionate quantity of them in the diamonds they market. Since the price of diamonds has been raised to the present high figure, there has been a noticeable willingness in the trade to overlook minor flaws. Dealers have been driven to the endeavor to show goods at a price which would appear reasonable compared with stones bought ten years ago. This effort to hide the wide difference of price for the same goods, that exists between now and then, has forced many dealers to accept imperfections which they would have refused formerly, in order to get stones at somewhere near old prices. Original parcels of perfect stones are rare now, nor will the importer allow the perfect ones to be taken from mixed lots, except at a very considerable advance. When the imperfections are slight, the parcel is quoted as ” clean.” If the buyer is persistent, he will learn that the lot contains a certain percentage of perfect stones and the balance is slightly piquè (which means they they have small specks or glasses in them), or perhaps that the entire parcel is slightly piquè. Other lots are said to ” run clean,” when a fair proportion are perfect or nearly so and some are quite imperfect. If a lot is admittedly imperfect, the imperfections will surely be quite noticeable. ” Rejections ” are the stones so badly imperfect as to endanger the sale of the lots from which they are culled. These are sold at a low figure to dealers in ” bargains.”
There are two kinds of imperfections or flaws : those which are inherent, and others arising from imperfect cutting.
Of the former, black, or carbon spots are the most discernible. They range from specks so small that it is difficult sometimes to discover them with a magnifying glass, to spots and broken, ragged clusters, quite plain to the naked eye. They are formed often of uncrystallized carbon or portions of the original element which did not crystallize with the rest but took one of the other forms of carbon, i. e. graphite or carbonado, probably the latter, and were included in that which did crystallize. Others are inclusions of foreign matter, titanic iron, etc. They are considered bad imperfections because they are so easily detected by the naked eye. It is worthy of observation, however, that the blackest and most abrupt carbon spots are usually found in the whitest and finest stones. They remind one of human nature, in which the flaws of great talent are more than ordinarily bad. Not only do black spots look blacker when set in material of peerless color and splendor, but they are blacker. Where carbon appears in the lower grade diamonds of Africa, it is often not only somewhat scattered, but cloudy and less distinct. In the pure white brilliant stones of India, it is decidedly black, and abruptly distinct in formation. Why the carbon inclusions failed to crystallize with the surrounding diamond, has not been satisfactorily explained. As they must have been subjected to the same heat and pressure as the remainder of the crystal, some other agency whose power was not equally distributed during the process of crystallization probably failed; again it may be necessary for the crystallization of carbon that it should be in a certain specific condition when the heat and pressure assumed to be requisite are applied. Rapid chemical action whereby carbon in solution is thrown down in trans-parent crystals; might surround particles which had escaped the solvent; on the other hand, the same result might be attained by the slow accretion of crystallized carbon atoms from a surrounding composite, to a nucleus of the element.
Sometimes these inclusions look like rough jagged pieces of carbonado, frequently surrounded by smaller detached pieces, but more often they resemble ink spots. Occasionally they appear like a thin cloud, as if a black powder were sprinkled over the face of a small fissure in the grain of the crystal. Some of them are fuzzy looking clusters, like little bunches of black dust. In other cases they appear as sharp hair lines, usually very short, occasionally broken at right angles, T shape, or like a check mark.
Small diamonds have been found in larger crystals. This fact, and the statement that the bursting of crystals is due to inclusions of compressed gas, led Mr. Williams to question the igneous theory of the genesis of the diamond and to favor the idea of the slow growth of large crystals by accretion, instead of a sudden solidification in a fused mass. One large diamond of 228 carats, found several years ago, was formed around a small red diamond crystal. In another case the smaller enclosed crystal was coated with apophylite.
White specks and bubbles are common flaws. These vary in size and appearance, some of them glistening in the interior with a vitreous luster, others ranging from an icy to snowy whiteness. Some of these, apparently, are hollow or gas-filled bubbles, while others are solid but imperfectly crystallized sections. Glessen or glasses, are flat sectional streaks of a similar nature, having an icy appearance. When large or abundant in a crystal, they constitute a very bad imperfection, as they destroy all but the surface brilliance of the stone. Diamonds of this character are sometimes termed ” shivery ” and in this country are difficult to sell at any price.
” Clouds ” are dark flat patches in the grain of the stone similar to the glasses, but brownish or blackish. Unlike glasses they are seldom large or numerous in a single stone, nor do they so completely destroy the internal brilliancy. They consist apparently of inclusions of foreign matter, or a fine dusting in the grain, of uncrystallized carbon. Some scientists claim that all black and brown spots and clouds are inclusions of foreign matter, probably titanic iron.
When clouds or glasses reach the surface of a cut diamond they appear as cracks, and if near the girdle are dangerous, the stone being liable to split there under heat or a smart blow. Usually the break will not extend throughout the stone but result in the loss of a sliver or a wedge-shaped piece out of the edge.
Many other inclusions have been noted by scientists, hematite being frequent. As the exact nature of these inclusions is of more interest from a scientific stand-point, they will not be discussed in this chapter, which considers them only as they affect the appearance of the cut stone to the eye, and the consequent effect on their desirability and value.
Surface flaws consist of nicks in the edge of the stone, or cavities in the face of one or more of the facets. It sometimes happens that irregularities in the surface of the crystal can be eliminated only by a considerable reduction of size in the finished stone. -If a depression exists where the edge or girdle will be, the cutter endeavors to cut it so that it will appear in the gem as an irregularity, which, though an imperfection of shape, would not constitute a flaw, but if the cavity, extends too far into the stone, the diamond leaves the polisher’s hands with a more or less observable nick in the edge. As the faces of many of these nicks are rough unpolished crystal, they not only spoil the perfection of outline, but detract materially from the beauty of the stone, and are in some cases reflected into the interior to its further detriment. In setting such stones, the jeweler is careful to hide these flaws as far as possible, by covering them with the gold prongs with which the stone is held. The prongs of a jewel often hide the reason why one stone costs less than another apparently no better.
Occasionally, uneven places in the crystal are where the face or back of the finished stone will be, and some of the cavities are so deep, that to cut all the material away necessary to reach the bottom of them, would en-tail a sacrifice of value by loss of weight greater than by the reduction of price per carat on account of the imperfections. They are therefore left, and become bad and deceptive flaws. While the stone is perfectly clean, they are not easily seen, but as soon as the jewel is worn, dust and grease get into the cavities and they appear as large ragged black flaws to mar the brilliancy of the stone. A stone of this character must be constantly washed, as rubbing over the surface, while it cleans the stone otherwise, at the same time deposits whatever dirt may be there, in the cavities, the edges of which act as scrapers every time the cloth or finger passes over them.
As a matter of sentiment, absolute perfection is desirable. To illustrate : a young man of means some years ago, wished to buy a pair of diamonds for the lady soon to be his wife. The retail jeweler to whom he applied, having nothing sufficiently fine in his stock, introduced him to a New York importer who chanced to be calling upon him. A certain engaging ingenuousness of manner enlisted the sympathies of the importer in the quest of his young customer which in turn begat confidence. In the New Yorker’s stock was a pair of blue Jagers diamonds of exquisite color and brilliancy, and perfectly cut. Taking them from his wallet, he showed them with the pleased anticipation of being able to satisfy fully a customer in whom he already felt a personal interest. The young man’s eyes sparkled at the sight of them, ” Ah ! That is what I want,” he exclaimed. Looking them over with smiling delight, he said further, ” They are just what I have been looking for.” Still toying with them, he asked casually, ” Are they perfect? ”
” One is, and the other is practically so,” said the dealer. ” There is in the edge of one, a small speck, so small indeed and so placed that it is almost impossible to find it with the loup,” he explained.
The young man’s smile faded. ” Too bad,” he sighed, ” I want a perfect pair.” Observing the dealer’s surprise, he said with a smile of excuse for his own unreasonably critical fancy, ” You see, I want them for the dearest girl on earth and I would never feel quite satisfied if I gave her anything which was not like herself, quite perfect. I do not mind the cost but they must be perpect.”
A similar sentiment only, justifies one in demanding absolute perfection where all other good qualities are so preeminent. Ordinarily, flaws which do not detract from the brilliancy of the stone and are not apparent to the eye, while they may be properly estimated in the valuation, should not be made to over-balance other and intrinsically valuable qualities. There are diamonds of such beauty that a few minor flaws are not an absolute bar to the favor of those who recognize their otherwise superior character. It is well to remember that an in-expert buyer is apt to give undue weight to faults which one who knows nothing of gems can discover. Flaws do not grow, but the inferior qualities of a poor stone do grow upon one by familiarity and comparison. Many people learn after they have purchased a stone because it had no flaws, that it ranks far below others which have, and become dissatisfied accordingly.
There are flawless stones which nevertheless appear to be flawed. This condition arises from faults of proportion whereby the rough edge or skin of the stone around the girdle is reflected into the interior of the diamond. It is usually found in stones which are cut too shallow on the culet side. If a diamond is not sufficiently deep from the girdle to the culet, a reflection of all rough places on the girdle will appear in the body of the stone. These reflections are not distinctly visible to the naked eye though they destroy to some extent the brilliancy of the jewel. Under the loup they become so prominent that one unaccustomed to them would think they existed in the stone. They are indisputable evidence that the stone is not cut so as to give the proper brilliancy, and diamonds of this character should be used only where a large surface effect at a minimum cost is wanted.
To find flaws, use a jeweler’s double loup with an inch focus; if that is not at hand, blow the breath quickly on the stone while it is cold, and search for them while the resulting mist lasts.