Popular Names. Certain more popular names for diamonds of differing degrees of whiteness may next be set forth. The term "blue white" (a much abused expression, by the way) should be applied only to diamonds of such a close approach to pure whiteness of body substance, as seen on edge in the paper that, when faced up and undimmed, they give such a strong play of prismatic blue that any slight trace of yellow in their substance is completely disguised, and the effect upon the eye is notably blue. This would be the case with stones of the grades from 1 through 4 in the list above. Grades 5 and 6 might properly be called "fine white," and grades 7, 8, and 9 simply "white." Grade 10 is frequently spoken of as "commercial white," and grade 11 sometimes as "off color." Grade 12 includes all degrees of brownness except the very light shades and the deep, pretty shades of the "fancy" browns.
Rubies. Leaving the naming of the different colors of diamonds we come to the gems furnished us by the mineral known as corundum. As we have previously seen, this mineral occurs in many different colors and with wide differences of tint and shade in each of the principal colors. The best practice with regard to naming the corundum gems is to call the red material, when of a good, full red of pleasing shade, ruby. The finest shades of blood red are usually called "Burmah rubies" because more rubies of this quality are found in Burmah than anywhere else. Any ruby of the required shade would, however, be called a Burmah ruby in the trade regardless of its geographical origin. The most desirable tint among Burmah rubies is that which is known as "pigeon blood" in color. This color is perhaps more accurately defined as like the color in the center of the red of the solar spectrum. Certain slightly deeper red rubies are said to be of "beef blood" color. The English are said to prefer these. Those of slightly lighter tint than pigeon blood are sometimes referred to as of "French color," from the fact that they are preferred by French connoisseurs.
Rubies of dark, garnet-like shade are known as "Siam rubies," many such being found in that country. Light pinkish rubies are called "Ceylon rubies." It should be clearly kept in mind that all these "rubies" are of red corundum, and that in all their distinctive properties except color they are essentially similar.
Sapphires. Corundum of fine blue color is known as "sapphire." The "cornflower blue" seems to be most in favor at present. Such sapphires are sometimes called "Kashmir sapphires" because many fine ones come from that State. "Ceylon sapphires" are usually paler than the cornflower blue. "Montana sapphires" are usually of greenish blue or pale electric blue. Such fine blue stones as are mined in Montana would be sold under another name according to the quality of their color, and not as "Montana sapphires." "Australian sapphires" are of a very deep, inky blue, and do not command a high price. Here again, as with rubies, the classification depends upon the color rather than upon the origin, although the geographical names that are used, correctly state the usual source of stones of the particular color.
All corundums other than ruby and blue sapphire are usually called by the term "sapphire," with a qualifying adjective designating the color; thus we may have pink sapphire, golden sapphire, green sapphire, etc. When of very fine yellow color the yellow sapphire is sometimes called "Oriental topaz" by jewelers, the term "Oriental" as thus used indicating that the material is corundum. We also have "Oriental amethyst" and "Oriental emerald" for the purple, and the fine green, and "Oriental aquamarine" for the light blue-green corundum. The yellow corundum is also sometimes called "King topaz," especially in Ceylon. Inferior sapphires of almost every conceivable color are frequently assorted in lots and sold as "fancy sapphires." Such lots, however, almost always need reclassification as they often contain as many as a dozen mineral species besides corundum.
Sapphires and rubies of minute tubular internal structure frequently display a beautiful six-pointed star when cut to a round-topped cabochon shape and exposed to direct sunlight or to light from any other single source. Such stones are named "star sapphire" and "star ruby."
The artificial rubies and sapphires should all be called scientific ruby or sapphire, and not "reconstructed" or "synthetic" as none are made to-day from small, real rubies, and as the process is in no sense a chemical synthesis.
Chrysoberyl. Leaving the corundum gems we come next to chrysoberyl. When the gems furnished by this mineral are of a fine green by daylight, and of a raspberry red by artificial light, as is sometimes the case, they should be called "Alexandrites" (after the Czar Alexander II., in whose dominions, and on whose birthday, the first specimens are said to have been discovered). When chrysoberyl is of fibrous or tubular internal structure it affords cat's-eyes (when cabochon cut), and these should be specifically named as "chrysoberyl cat's-eye" to distinguish them from the less beautiful and less valuable quartz cat's-eyes. Other varieties of chrysoberyl (most of those marketed are of a greenish-yellow color) are correctly named simply "chrysoberyls." Such stones are, however, sometimes incorrectly called "chrysolite" by the trade, and this practice should be corrected, as the term chrysolite applies correctly only to the mineral olivine which gives us the peridot.
Spinel. Next in the order that we have chosen comes "spinel." The more valuable spinels are of a red color that somewhat closely approaches the red of some rubies. Such red spinels should be called "Ruby spinel" (and not spinel ruby). The stones themselves sometimes get mixed with corundum rubies (they are frequently found in the same gem gravels), and this makes it all the more necessary that both stones and names should be clearly distinguished. Some dealers call reddish spinels "Balas ruby" (rose red), and orange red ones "rubicelle." Violet red spinel is sometimes called "almandine spinel." It is very desirable that the name of the mineral species, spinel, should be used, together with a qualifying color adjective, in naming gems of this species, rather than such terms as "rubicelle," "balas ruby," "spinel ruby," etc.
Topaz. We come now to topaz. True, or precious topaz, as it is usually called, to distinguish it from the softer and less valuable yellow quartz, is seldom seen in the trade to-day. Jewelers almost always mean yellow quartz when they speak of "topaz." This is an unfortunate confusion of terms, and one which will be hard to eradicate. There is seldom any injustice done through this misnaming, as the price charged is usually a fair one for the material offered. Considerably higher prices would be necessary if true topaz was in question.